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Grammage

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Grammage and basis weight, in the pulp and paper industry, are the area density of a paper product, that is, its mass per unit of area. Two ways of expressing the area density of a paper product are commonly used:

  • Expressed in grams (g) per square metre (g/m2), regardless of its thickness (caliper)[1] (known as grammage). This is the measure used in most parts of the world. It is often notated as gsm on paper product labels and spec sheets.
  • Expressed in terms of the mass per number of sheets of a specific paper size (known as basis weight). The convention used in the United States and a few other countries using US-standard paper sizes is pounds (lb) per ream of 500 (or in some cases 1000) sheets of a given (raw, still uncut) basis size. The traditional British practice is pounds per ream of 480, 500, 504, or 516 sheets of a given basis size. Japanese paper is expressed as the weight in kilograms (kg) per 1,000 sheets.

Grammage

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In the metric system, the mass per unit area of all types of paper and paperboard is expressed in terms of grams per square metre (g/m2). This quantity is commonly called grammage in both English and French,[2] though printers in most English-speaking countries still refer to the "weight" of paper.

Typical office paper has 80 g/m2 (0.26 oz/sq ft), therefore a typical A4 sheet (116 of a square metre) weighs 5 g (0.18 oz). The abbreviation "gsm" instead of the standard g/m2 symbol is also widely encountered in English-speaking countries.

Typically grammage is measured in paper mill on-line by a quality control system and verified by laboratory measurement.

Basis weight

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Basis weight of paper is the density of paper expressed in terms of the mass (in pound) of a ream of paper of given dimensions and a sheet count. The American and the traditional British systems are largely the same, with only minor differences: the paper dimensions and the sheet count are different.

United States

[edit]

In the US system, the weight is specified in avoirdupois pounds and the sheet count of a paper ream is usually 500 sheets. However, the mass specified is not the mass of the ream that is sold to the customer. Instead, it is the mass of the uncut "basis ream" in which the sheets have some larger size (parent size). Often, that is a size used during the manufacturing process before the paper is cut to the dimensions in which it is sold. So, to compute the mass per area, one must know

  • the mass of the basis ream,
  • the number of sheets in that ream, and
  • the dimensions of an "uncut" sheet in that ream.

The standard dimensions and sheet count of a ream vary according to the type of paper. These "uncut" basis sizes are not normally labelled on the product, are not formally standardized, and therefore have to be guessed or inferred somehow from trading practice. Historically, this convention is the product of pragmatic considerations such as the size of a sheet mold.

By using the same basis sheet size for the same type of paper, consumers can easily compare papers of differing brands. Twenty-pound bond paper is always lighter and thinner than 32-pound bond, no matter what its cut size, and 20-pound bond letter size and 20-pound bond legal size papers are the same weight paper with a different cut size.

However, a sheet of common copy paper that has a basis weight of 20 pounds (9.1 kg) does not have the same mass as the same size sheet of coarse paper (newsprint). In the former case, the standard ream is 500 sheets of 17-by-22-inch (432 by 559 mm) paper, and in the latter, 500 sheets of 24-by-36-inch (610 by 914 mm) paper. Here are some basic ream sizes for various types of paper. Units are inches except where noted.

Paper type Paper size
(inches)
Sheets per ream
Bond, writing, ledger 17 × 22 500
Manuscript cover 18 × 31 500
Blotting 19 × 24 500
Box cover 20 × 24 500
Cover 20 × 26 500 or 1000
Watercolour 22 × 30 500
Bristol and tag 22+12 × 28+12 500
Tissue 24 × 36 480
Newsprint 24 × 36 500
Hanging, waxing, bag, etc. 24 × 36 500
Book, text, offset 25 × 38 500
Index bristol 25+12 × 30+12 500
Paperboard (all types) 12 × 12 1000 (1000 sq ft per ream)

Sheets 17 by 22 inches (432 by 559 mm) can be cut into four 8+12-by-11-inch (216 by 279 mm) sheets, a standard for business stationery known conventionally as letter sized paper. So, the 17-by-22-inch (432 by 559 mm) ream became commonly used. The 25-by-38-inch (635 by 965 mm) book-paper ream developed because such a size can easily be cut into sixteen 6-by-9-inch (152 by 229 mm) book sized sheets without significant waste (nominally 6+14-by-9+12-inch (159 by 241 mm) before trimming and binding).

Early newsprint presses printed sheets 2 by 3 feet (610 by 914 mm) in size, and so the ream dimensions for newsprint became 24 by 36 inches (610 by 914 mm), with 500 sheets to a ream. Newsprint was made from ground wood pulp, and ground wood hanging paper (wallpaper) was made on newsprint machines. Newsprint was used as wrapping paper, and the first paper bags were made from newsprint. The newsprint ream standard also became the standard for packaging papers, even though in packaging papers kraft pulp, rather than ground wood, was used for greater strength.

Paper weight is sometimes stated using the "#" symbol. For example, "20#" means "20 pounds per basis ream of that kind of paper". When the density of a ream of paper is given in pounds, it is often accompanied by its "M weight" (M is 1000 in Roman numerals). The M weight is the weight (in pounds) of 1000 cut sheets. Paper suppliers will often charge by M weight, since it is always consistent within a specific paper size, and because it allows a simple weight calculation for shipping charges.

For example, a 500-sheet ream of 20# 8+12-by-11-inch (216 by 279 mm) copy paper may be specified "10 M". 1000 cut sheets (or two reams) will weigh 10 lb (4.5 kg), half of the four reams of cut paper resulting from the 20# basis ream of 17-by-22-inch (432 by 559 mm) paper.

United Kingdom

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Overview of the traditional British system

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Like the American system, the traditional British system also involves the use of basis weight to express the area density of paper (and, indirectly, paper thickness) in the course of buying and selling paper. The British paper industry exclusively used basis weight before adopting grammage in 1971.[3]

In the traditional British system, basis weight is also expressed in terms of the weight of an imaginary ream of paper of a certain size.  The underlying concept is that a ream of paper of the stated paper size and of the same thickness as the paper the parties are dealing with would have the stated weight. The weight is expressed in pound. As to paper sizes (basis sizes), they can, theoretically, be any sizes, but, by custom, a number of common sizes emerged. In the 1960s, even the metric A1[4] and A2[5] had been used as basis sizes alongside the British ones.

The following are common[6][7][8] British basis sizes (sizes of British uncut paper):

Common British basis sizes
Note 1:
The Italicised writing‑paper and printing‑paper sizes were in use only prior to the 1925 standardisation[9] of writing‑paper and printing‑paper sizes. The 1925 standardisation did not apply to wrapping‑paper sizes.

Note 2:
The underlined writing‑paper and printing‑paper sizes were in use after the 1925 standardisation but were not adopted as standard sizes[10] by British Standards Institution specification number 730 of 1937.

Note 3:
The wrapping‑paper sizes marked with ‘*’ were not adopted as standard sizes by British Standards Institution specification number 730 of 1937.[10]

Writing paper
Atlas 26″ × 34″
Copy 161/2″ × 20″
Double elephant

(adopted by British Standards Institution specification number 730 of 1937 but not the 1925 standardisation)

27″ × 40″
Double imperial 30″ × 44″
Double large post 21″ × 33″
Double post

(adopted by British Standards Institution specification number 730 of 1937 but not the 1925 standardisation)

19″ × 30″

(prior to re‑definition by British Standards Institution specification number 730 of 1937, 19″ × 301/2″)

Double pott 15″ × 25″
Double small demy

(known as ‘double demy’ before the 1925 standardisation)

20″ × 31″
Double small foolscap

(known as ‘double foolscap’ before British Standards Institution specification number 730 of 1937)

(‘foolscap’ is sometimes shortened to ‘’cap’ or ‘cap’)

161/2″ × 261/2
Double small royal

(known as ‘double royal’ before the 1925 standardisation)

24″ × 38″
Elephant 23″ × 28″
Imperial 22″ × 30″
Large post 161/2″ × 21″
Pinched post 143/4″ × 181/2
Post

(adopted by British Standards Institution specification number 730 of 1937 but not the 1925 standardisation)

15″ × 19″

(prior to re‑definition by British Standards Institution specification number 730 of 1937, 151/4″ ×19″)

Pott 121/2″ × 15″
Sheet‑and‑a‑half small foolscap

(known as ‘sheet‑and‑a‑half foolscap’ before British Standards Institution specification number 730 of 1937)

(‘foolscap’ is sometimes shortened to ‘’cap’ or ‘cap’)

131/4″ × 243/4

(before the 1925 standardisation, 131/4″ × 241/2″)

Sheet‑and‑a‑third small foolscap

(introduced by the 1925 standardisation)

(known as ‘sheet‑and‑a‑third foolscap’ before British Standards Institution specification number 730 of 1937)

(‘foolscap’ is sometimes shortened to ‘’cap’ or ‘cap’)

131/4″ × 22″
Small demy

(known as ‘demy’ before the 1925 standardisation)

151/2″ × 20″
Small foolscap

(known as ‘foolscap’ before British Standards Institution specification number 730 of 1937)

(‘foolscap’ is sometimes shortened to ‘’cap’ or ‘cap’)

131/4″ × 161/2
Small medium

(known as ‘medium’ before the 1925 standardisation)

171/2″ × 22″
Small post

(introduced by the 1925 standardisation)

141/2″ × 181/2
Small royal

(known as ‘royal’ before the 1925 standardisation)

19″ × 24″
Super royal 19″ × 27″

(before the 1925 standardisation, 191/4″ × 27″)

Printing paper
Copy 161/2″ × 20″
Crown 15″ × 20″
Demy 171/2″ × 221/2
Double crown 20″ × 30″
Double demy 221/2″ × 35″
Double elephant

(also known as ‘double large royal’)

(adopted by British Standards Institution specification number 730 of 1937 but not the 1925 standardisation)

27″ × 40″
Double globe 28″ × 38″
Double imperial 30″ × 44″
Double foolscap

(known as ‘double large foolscap’ after the 1925 standardisation and before being re‑named by British Standards Institution specification number 730 of 1937)

(‘foolscap’ is sometimes shortened to ‘’cap’ or ‘cap’)

17″ × 27″
Double large post 21″ × 33″
Double medium 23″ × 36″
Double post

(adopted by British Standards Institution specification number 730 of 1937 but not the 1925 standardisation)

19″ × 30″

(prior to re‑definition by British Standards Institution specification number 730 of 1937, 191/4″ × 311/2″)

Double pott 15″ × 25″
Double royal 25″ × 40″
Elephant 23″ × 28″
Foolscap

(known as ‘large foolscap’ after the 1925 standardisation and before being re‑named by British Standards Institution specification number 730 of 1937)

(‘foolscap’ is sometimes shortened to ‘’cap’ or ‘cap’)

131/2″ × 17″
Imperial 22″ × 30″
Large post 161/2″ × 21″
Large royal

(introduced by the 1925 standardisation)

201/2″ × 27″

(prior to re‑definition by British Standards Institution specification number 730 of 1937, 20″ × 27″)

Medium 18″ × 23″
Music demy 143/8″ × 203/4
Post

(adopted by British Standards Institution specification number 730 of 1937 but not the 1925 standardisation)

15″ × 19″

(prior to re‑definition by British Standards Institution specification number 730 of 1937, 151/2″ × 191/4″)

Pott 121/2″ × 15″
Quad crown 30″ × 40″
Quad demy 35″ × 45″
Quad foolscap

(known as ‘quad large foolscap’ after the 1925 standardisation and before being re‑named by British Standards Institution specification number 730 of 1937)

(‘foolscap’ is sometimes shortened to ‘’cap’ or ‘cap’)

27″ × 34″
Quad globe 38″ × 56″
Quad pott 25″ × 30″
Quad royal 40″ × 50″
Royal 20″ × 25″
Super royal 201/2″ × 271/2
Wrapping paper
Bag cap 20″ × 24″

(prior to re‑definition by British Standards Institution specification number 730 of 1937, 191/2″ × 24″)

Casing 36″ × 46″

(across the island of Ireland, 36″ × 48″)

Double bag cap* 24″ × 39″*
Double crown 20″ × 30″
Double double imperial 45″ × 58″
Double elephant* 31″ × 46″*
Double imperial 29″ × 45″
Double medium 23″ × 36″
Double small cap* 25″ × 34″*
Double small hand* 20″ × 29″*
Elephant* 24″ × 32″*
Extra large casing 40″ × 48″
Haven cap*

(sometimes called ‘havon cap’)

21″ × 26″*
Imperial 221/2″ × 29″
Kent cap* 18″ × 21″*
Lumber hand* 171/2″ × 221/2″*
Quad crown 30″ × 40″
Quad foolscap*

(known as ‘quad large foolscap’ after the 1925 standardisation and before British Standards Institution specification number 730 of 1937)

(the word, ‘foolscap’, is sometimes shortened to ‘’cap’ or ‘cap’)

27″ × 34″*
Quad royal* 40″ × 50″*
Quad small hand* 30″ × 40″*
Royal* 20″ × 25″*
Saddleback 36″ × 45″
Small cap* 17″ × 25″*
Small hand* 15″ × 20″*
(No name) 20″ × 24″*
(No name) 20″ × 28″*
(No name) 21″ × 31″*
(No name) 21″ × 34″*
(No name) 22″ × 32″*
(No name) 22″ × 35″*
(No name) 23″ × 34″*
(No name) 24″ × 30″*
(No name) 24″ × 36″*
(No name) 24″ × 40″*
(No name) 26″ × 36″*
(No name) 28″ × 45″*
(No name) 29″ × 44″*
(No name) 30″ × 38″*
(No name) 30″ × 46″*
(No name) 34″ × 36″*
(No name) 36″ × 36″*
(No name) 36″ × 48″*
(No name) 38″ × 48″*
(No name) 45″ × 56″*

One ream in the context of basis weight (basis ream) can be 480 sheets, 500 sheets, 504 sheets, or 516 sheets: there is no fixed rule on when a certain definition was applied; however, starting from the 1950s,[11] the trend of moving towards 500 sheets emerged.

Basis weight is commonly expressed in terms of pound per ream of paper of a certain size, in the format of ‘[number]lb [paper size]’ (e. g., ‘21lb large post’ (‘21 pounds per ream of large post paper’)). Since there are basis reams of different sizes, unless the context leaves no room for ambiguity, the number of sheets in the basis ream is also given after the paper size to avoid misunderstanding: in such case, basis weight is expressed in the format of ‘[number]lb [paper size] [number of sheets of paper in the basis ream]’, such as ‘21lb large post 480’ (‘21 pounds per 480‑sheet ream of large post paper’). In the United Kingdom, ‘#’ has never been used to express paper weight because it is called ‘hash’, instead of ‘pound’, in British English.

Demy traditionally plays the role of the default basis size for expressing basis weights: in the British paper industry, there was a device, called ‘demy scale’, that was used to measure the weights of different paper samples in pound per ream of demy paper (480‑sheet, 500‑sheet, and 516‑sheet reams).[12]

Below is a list of common[11] basis weights of paper stocked by British paper merchants:

Common British basis weights and their metric and American equivalents
Writing paper
Common British basis weights

(various paper sizes and ream sizes)

Equivalent weight of a 500‑sheet ream of large post paper, a British uncut writing paper commonly used to express the basis weight of writing paper

(rounded to the nearest quarter)

(a common British basis for intra‑category comparison)

Equivalent weight of a 500‑sheet ream of demy paper, a British uncut printing paper commonly used by default to express the basis weight of different types of paper[a]

(rounded to the nearest quarter)

(a common British basis for cross‑category comparison)

Equivalent grammage

(rounded to the nearest one)

Equivalent weight of a 500‑sheet ream of bond paper, an American uncut paper commonly used to express the basis weight of paper

(rounded to the nearest quarter)

(a common American basis for cross‑category comparison)

11lb large post 480 111/2lb large post 13lb demy 46gsm 121/4lb bond
11lb large post 500 11lb large post 121/2lb demy 45gsm 113/4lb bond
12lb large post 500 12lb large post 131/2lb demy 49gsm 13lb bond
14lb large post 480 141/2lb large post 161/2lb demy 59gsm 153/4lb bond
15lb large post 480 153/4lb large post 173/4lb demy 63gsm 163/4lb bond
15lb large post 500 15lb large post 17lb demy 61gsm 161/4lb bond
15lb large post 504 15lb large post 17lb demy 60gsm 16lb bond
17lb large post 480 173/4lb large post 20lb demy 72gsm 19lb bond
18lb large post 480 183/4lb large post 211/2lb demy 76gsm 201/4lb bond
18lb large post 500 18lb large post 201/2lb demy 73gsm 191/2lb bond
18lb large post 504 173/4lb large post 201/4lb demy 72gsm 191/4lb bond
19lb large post 480 193/4lb large post 221/2lb demy 80gsm 211/4lb bond
20lb large post 480 203/4lb large post 233/4lb demy 85gsm 221/2lb bond
21lb large post 480 22lb large post 243/4lb demy 89gsm 231/2lb bond
21lb large post 500 21lb large post 233/4lb demy 85gsm 223/4lb bond
21lb large post 504 203/4lb large post 233/4lb demy 85gsm 221/2lb bond
22lb large post 480 23lb large post 26lb demy 93gsm 243/4lb bond
22lb large post 504 213/4lb large post 243/4lb demy 89gsm 231/2lb bond
23lb large post 480 24lb large post 271/4lb demy 97gsm 253/4lb bond
23lb large post 500 23lb large post 261/4lb demy 93gsm 243/4lb bond
23lb large post 504 223/4lb large post 26lb demy 93gsm 241/2lb bond
24lb large post 480 25lb large post 281/2lb demy 101gsm 27lb bond
24lb large post 504 233/4lb large post 27lb demy 97gsm 253/4lb bond
25lb large post 480 26lb large post 291/2lb demy 106gsm 28lb bond
25lb large post 500 25lb large post 281/2lb demy 101gsm 27lb bond
26lb large post 480 27lb large post 303/4lb demy 110gsm 291/4lb bond
26lb large post 504 253/4lb large post 291/4lb demy 105gsm 273/4lb bond
27lb large post 480 281/4lb large post 32lb demy 114gsm 301/4lb bond
27lb large post 504 263/4lb large post 301/2lb demy 109gsm 29lb bond
28lb large post 480 291/4lb large post 331/4lb demy 118gsm 311/2lb bond
28lb large post 504 273/4lb large post 311/2lb demy 113gsm 30lb bond
30lb large post 480 311/4lb large post 351/2lb demy 127gsm 333/4lb bond
22lb double large post 500 11lb large post 121/2lb demy 45gsm 113/4lb bond
30lb double large post 480 153/4lb large post 173/4lb demy 63gsm 163/4lb bond
30lb double large post 500 15lb large post 17lb demy 61gsm 161/4lb bond
30lb double large post 504 15lb large post 17lb demy 60gsm 16lb bond
36lb double large post 480 183/4lb large post 211/4lb demy 76gsm 201/4lb bond
36lb double large post 500 18lb large post 201/2lb demy 73gsm 191/2lb bond
36lb double large post 504 173/4lb large post 201/4lb demy 72gsm 191/4lb bond
42lb double large post 480 22lb large post 243/4lb demy 89gsm 231/2lb bond
42lb double large post 500 21lb large post 233/4lb demy 85gsm 223/4lb bond
42lb double large post 504 203/4lb large post 233/4lb demy 85gsm 221/2lb bond
44lb double large post 504 213/4lb large post 243/4lb demy 89gsm 231/2lb bond
13lb small medium 480 121/4lb large post 133/4lb demy 49gsm 13lb bond
18lb small medium 480 17lb large post 191/4lb demy 68gsm 181/4lb bond
21lb small medium 504 183/4lb large post 211/4lb demy 76gsm 201/4lb bond
211/2lb small medium 500 191/4lb large post 22lb demy 79gsm 21lb bond
23lb small medium 480 211/2lb large post 241/2lb demy 88gsm 231/4lb bond
23lb small medium 504 201/2lb large post 231/4lb demy 83gsm 22lb bond
24lb small medium 504 211/2lb large post 241/4lb demy 87gsm 231/4lb bond
25lb small medium 480 231/2lb large post 263/4lb demy 95gsm 251/4lb bond
25lb small medium 504 221/4lb large post 251/4lb demy 91gsm 24lb bond
30lb small medium 516 261/4lb large post 293/4lb demy 106gsm 281/4lb bond
34lb small medium 480 32lb large post 361/4lb demy 129gsm 341/2lb bond
40lb small medium 504 353/4lb large post 401/2lb demy 145gsm 381/2lb bond
13lb medium 500 11lb large post 121/4lb demy 44gsm 113/4lb bond
14lb medium 500 121/2lb large post 131/4lb demy 51gsm 131/2lb bond
18lb medium 480 153/4lb large post 173/4lb demy 64gsm 17lb bond
18lb medium 500 15lb large post 17lb demy 61gsm 161/4lb bond
21lb medium 500 171/2lb large post 20lb demy 71gsm 19lb bond
211/2lb medium 500 18lb large post 201/2lb demy 73gsm 191/2lb bond
25lb medium 500 21lb large post 233/4lb demy 85gsm 221/2lb bond
28lb medium 500 231/2lb large post 263/4lb demy 95gsm 251/4lb bond
26lb double medium 500 11lb large post 121/4lb demy 44gsm 113/4lb bond
36lb double medium 500 15lb large post 17lb demy 61gsm 161/4lb bond
46lb double medium 480 20lb large post 223/4lb demy 81gsm 213/4lb bond
46lb double medium 504 19lb large post 213/4lb demy 77gsm 201/2lb bond
48lb double medium 504 20lb large post 223/4lb demy 81gsm 211/2lb bond
50lb double medium 504 203/4lb large post 231/2lb demy 84gsm 221/2lb bond
60lb double medium 480 261/4lb large post 293/4lb demy 106gsm 281/4lb bond
60lb double medium 500 25lb large post 281/2lb demy 102gsm 27lb bond
70lb double medium 500 291/4lb large post 331/4lb demy 119gsm 311/2lb bond
20lb double small foolscap 500 153/4lb large post 18lb demy 64gsm 17lb bond
24lb double small foolscap 480 193/4lb large post 221/2lb demy 80gsm 211/2lb bond
24lb double small foolscap 500 19lb large post 211/2lb demy 77gsm 201/2lb bond
25lb double small foolscap 480 203/4lb large post 231/2lb demy 84gsm 221/4lb bond
26lb double small foolscap 504 201/2lb large post 231/4lb demy 83gsm 22lb bond
28lb double small foolscap 480 23lb large post 261/4lb demy 94gsm 25lb bond
28lb double small foolscap 500 221/4lb large post 251/2lb demy 90gsm 24lb bond
28lb double small foolscap 504 22lb large post 25lb demy 89gsm 233/4lb bond
30lb double small foolscap 480 243/4lb large post 281/4lb demy 100gsm 263/4lb bond
30lb double small foolscap 504 231/2lb large post 263/4lb demy 96gsm 251/2lb bond
32lb double small foolscap 504 251/4lb large post 281/2lb demy 102gsm 271/4lb bond
34lb double small foolscap 504 263/4lb large post 301/4lb demy 108gsm 283/4lb bond
36lb double small foolscap 480 293/4lb large post 333/4lb demy 121gsm 32lb bond
141/2lb double foolscap 480 111/2lb large post 13lb demy 46gsm 121/4lb bond
141/2lb double foolscap 500 11lb large post 121/2lb demy 44gsm 113/4lb bond
20lb double foolscap 480 153/4lb large post 173/4lb demy 64gsm 17lb bond
20lb double foolscap 500 15lb large post 171/4lb demy 61gsm 161/4lb bond
24lb double foolscap 480 19lb large post 211/2lb demy 77gsm 201/4lb bond
24lb double foolscap 500 18lb large post 201/2lb demy 74gsm 191/2lb bond
28lb double foolscap 500 211/4lb large post 24lb demy 86gsm 223/4lb bond
30lb double crown 500 171/4lb large post 193/4lb demy 70gsm 183/4lb bond
32lb double crown 480 191/4lb large post 22lb demy 78gsm 203/4lb bond
32lb double crown 504 181/4lb large post 203/4lb demy 74gsm 193/4lb bond
36lb double crown 500 203/4lb large post 233/4lb demy 84gsm 221/2lb bond
40lb double crown 500 23lb large post 261/4lb demy 94gsm 25lb bond
40lb double crown 504 23lb large post 26lb demy 93gsm 243/4lb bond
44lb double crown 500 251/2lb large post 29lb demy 103gsm 271/2lb bond
46lb double crown 480 273/4lb large post 311/2lb demy 112gsm 293/4lb bond
50lb double crown 500 283/4lb large post 323/4lb demy 117gsm 311/4lb bond
60lb double crown 504 341/2lb large post 39lb demy 139gsm 37lb bond
88lb quad crown 500 251/2lb large post 29lb demy 103gsm 271/2lb bond
100lb quad crown 500 283/4lb large post 323/4lb demy 117gsm 311/4lb bond
25lb small demy 480 29lb large post 33lb demy 118gsm 311/2lb bond
38lb small demy 480 441/4lb large post 501/4lb demy 180gsm 473/4lb bond
18lb small foolscap 480 293/4lb large post 333/4lb demy 121gsm 32lb bond
48lb quad foolscap 504 18lb large post 201/2lb demy 73gsm 191/2lb bond
50lb quad foolscap 480 193/4lb large post 221/4lb demy 80gsm 211/4lb bond
72lb imperial (writing and printing) 480 391/2lb large post 443/4lb demy 160gsm 421/2lb bond
18lb post (writing) (pre–‍1937 standardisation) 480 221/2lb large post 251/2lb demy 91gsm 241/4lb bond
20lb post (writing) (pre–‍1937 standardisation) 480 25lb large post 281/4lb demy 101gsm 27lb bond
22lb post (writing) (pre–‍1937 standardisation) 480 271/2lb large post 311/4lb demy 111gsm 291/2lb bond
72lb quad large post 504 173/4lb large post 201/4lb demy 72gsm 191/4lb bond
84lb quad large post 480 22lb large post 243/4lb demy 89gsm 231/2lb bond
29lb pinched post 480 381/4lb large post 431/2lb demy 156gsm 411/2lb bond
44lb small royal 480 343/4lb large post 391/2lb demy 141gsm 371/2lb bond
54lb super royal (writing) (pre–‍1925 standardisation) 480 371/2lb large post 421/2lb demy 152gsm 401/2lb bond
Printing paper
Common British basis weights

(various paper sizes and ream sizes)

Equivalent weight of a 500‑sheet ream of double crown paper, a British uncut printing paper commonly used to express the basis weight of printing paper

(rounded to the nearest quarter)

(a common British basis for intra‑category comparison)

Equivalent weight of a 500‑sheet ream of demy paper, a British uncut printing paper commonly used by default to express the basis weight of different types of paper[a]

(rounded to the nearest quarter)

(a common British basis for cross‑category comparison)

Equivalent grammage

(rounded to the nearest one)

Equivalent weight of a 500‑sheet ream of bond paper, an American uncut paper commonly used to express the basis weight of paper

(rounded to the nearest quarter)

(a common American basis for cross‑category comparison)

17lb double crown 480 173/4lb double crown 111/2lb demy 42gsm 11lb bond
19lb double crown 480 193/4lb double crown 13lb demy 46gsm 121/4lb bond
20lb double crown 480 203/4lb double crown 133/4lb demy 49gsm 13lb bond
20lb double crown 516 191/2lb double crown 123/4lb demy 45gsm 12lb bond
21lb double crown 480 22lb double crown 141/4lb demy 51gsm 133/4lb bond
22lb double crown 480 23lb double crown 15lb demy 54gsm 141/4lb bond
23lb double crown 480 24lb double crown 153/4lb demy 56gsm 15lb bond
23lb double crown 504 223/4lb double crown 15lb demy 53gsm 141/4lb bond
24lb double crown 504 233/4lb double crown 153/4lb demy 56gsm 143/4lb bond
24lb double crown 516 231/4lb double crown 151/4lb demy 55gsm 141/2lb bond
25lb double crown 480 26lb double crown 17lb demy 61gsm 161/4lb bond
25lb double crown 504 243/4lb double crown 161/4lb demy 58gsm 151/2lb bond
26lb double crown 480 27lb double crown 173/4lb demy 63gsm 163/4lb bond
26lb double crown 504 253/4lb double crown 17lb demy 60gsm 16lb bond
26lb double crown 516 251/4lb double crown 161/2lb demy 59gsm 153/4lb bond
27lb double crown 480 281/2lb double crown 181/2lb demy 66gsm 171/2lb bond
27lb double crown 500 27lb double crown 173/4lb demy 63gsm 163/4lb bond
27lb double crown 504 263/4lb double crown 171/2lb demy 63gsm 163/4lb bond
28lb double crown 480 291/4lb double crown 191/4lb demy 68gsm 181/4lb bond
28lb double crown 516 271/4lb double crown 173/4lb demy 64gsm 17lb bond
29lb double crown 480 301/4lb double crown 193/4lb demy 71gsm 183/4lb bond
30lb double crown 480 311/4lb double crown 201/2lb demy 73gsm 191/2lb bond
30lb double crown 500 30lb double crown 193/4lb demy 70gsm 183/4lb bond
30lb double crown 504 293/4lb double crown 191/2lb demy 70gsm 181/2lb bond
30lb double crown 516 29lb double crown 19lb demy 68gsm 18lb bond
31lb double crown 504 303/4lb double crown 201/4lb demy 72gsm 191/4lb bond
32lb double crown 480 331/4lb double crown 22lb demy 78gsm 203/4lb bond
32lb double crown 504 313/4lb double crown 203/4lb demy 74gsm 193/4lb bond
32lb double crown 516 31lb double crown 201/4lb demy 73gsm 191/4lb bond
33lb double crown 480 35lb double crown 221/2lb demy 81gsm 211/2lb bond
33lb double crown 504 323/4lb double crown 211/2lb demy 77gsm 201/2lb bond
34lb double crown 504 333/4lb double crown 221/4lb demy 79gsm 21lb bond
34lb double crown 516 33lb double crown 211/2lb demy 77gsm 201/2lb bond
35lb double crown 480 361/2lb double crown 24lb demy 85gsm 223/4lb bond
36lb double crown 480 371/2lb double crown 241/2lb demy 88gsm 231/2lb bond
36lb double crown 500 36lb double crown 233/4lb demy 84gsm 221/2lb bond
36lb double crown 504 353/4lb double crown 231/2lb demy 84gsm 221/4lb bond
36lb double crown 516 35lb double crown 23lb demy 82gsm 213/4lb bond
38lb double crown 480 391/2lb double crown 26lb demy 93gsm 243/4lb bond
38lb double crown 504 373/4lb double crown 243/4lb demy 88gsm 231/2lb bond
38lb double crown 516 363/4lb double crown 241/4lb demy 86gsm 23lb bond
39lb double crown 504 383/4lb double crown 251/2lb demy 91gsm 24lb bond
40lb double crown 480 413/4lb double crown 271/4lb demy 98gsm 26lb bond
40lb double crown 500 40lb double crown 261/4lb demy 94gsm 25lb bond
40lb double crown 504 393/4lb double crown 26lb demy 93gsm 243/4lb bond
40lb double crown 516 383/4lb double crown 251/2lb demy 91gsm 241/4lb bond
42lb double crown 480 433/4lb double crown 283/4lb demy 103gsm 271/4lb bond
42lb double crown 504 413/4lb double crown 271/4lb demy 98gsm 26lb bond
44lb double crown 480 453/4lb double crown 30lb demy 107gsm 281/2lb bond
44lb double crown 500 44lb double crown 283/4lb demy 103gsm 271/2lb bond
44lb double crown 516 423/4lb double crown 28lb demy 100gsm 261/2lb bond
45lb double crown 480 47lb double crown 303/4lb demy 110gsm 291/4lb bond
45lb double crown 500 45lb double crown 291/2lb demy 105gsm 28lb bond
46lb double crown 480 48lb double crown 311/2lb demy 112gsm 293/4lb bond
46lb double crown 504 453/4lb double crown 30lb demy 107gsm 281/2lb bond
46lb double crown 516 441/2lb double crown 291/4lb demy 104gsm 273/4lb bond
47lb double crown 480 49lb double crown 32lb demy 115gsm 301/2lb bond
50lb double crown 480 52lb double crown 341/4lb demy 122gsm 321/2lb bond
50lb double crown 500 50lb double crown 323/4lb demy 117gsm 311/4lb bond
50lb double crown 504 491/2lb double crown 321/2lb demy 116gsm 31lb bond
50lb double crown 516 481/2lb double crown 313/4lb demy 114gsm 301/4lb bond
52lb double crown 480 541/4lb double crown 351/2lb demy 127gsm 333/4lb bond
54lb double crown 480 561/4lb double crown 37lb demy 132gsm 35lb bond
54lb double crown 516 521/4lb double crown 341/4lb demy 123gsm 321/2lb bond
55lb double crown 480 571/4lb double crown 371/2lb demy 134gsm 353/4lb bond
56lb double crown 516 541/4lb double crown 351/2lb demy 127gsm 333/4lb bond
57lb double crown 480 591/2lb double crown 39lb demy 139gsm 37lb bond
58lb double crown 500 58lb double crown 38lb demy 136gsm 361/4lb bond
60lb double crown 480 621/2lb double crown 41lb demy 146gsm 39lb bond
60lb double crown 500 60lb double crown 391/2lb demy 141gsm 371/2lb bond
60lb double crown 504 591/2lb double crown 39lb demy 139gsm 37lb bond
60lb double crown 516 581/4lb double crown 381/4lb demy 136gsm 361/4lb bond
61lb double crown 480 631/2lb double crown 413/4lb demy 149gsm 391/2lb bond
76lb double crown 480 791/4lb double crown 52lb demy 186gsm 491/4lb bond
79lb double crown 516 761/2lb double crown 501/4lb demy 179gsm 473/4lb bond
80lb double crown 480 831/4lb double crown 543/4lb demy 195gsm 52lb bond
80lb double crown 504 791/4lb double crown 52lb demy 186gsm 491/2lb bond
40lb quad crown 516 191/2lb double crown 123/4lb demy 45gsm 12lb bond
48lb quad crown 504 233/4lb double crown 153/4lb demy 56gsm 143/4lb bond
50lb quad crown 480 26lb double crown 17lb demy 61gsm 161/4lb bond
54lb quad crown 500 27lb double crown 173/4lb demy 63gsm 163/4lb bond
60lb quad crown 480 311/4lb double crown 201/2lb demy 73gsm 191/2lb bond
60lb quad crown 500 30lb double crown 193/4lb demy 70gsm 183/4lb bond
60lb quad crown 504 293/4lb double crown 191/2lb demy 70gsm 181/2lb bond
60lb quad crown 516 29lb double crown 19lb demy 68gsm 18lb bond
64lb quad crown 516 31lb double crown 201/4lb demy 73gsm 191/4lb bond
68lb quad crown 516 33lb double crown 211/2lb demy 77gsm 201/2lb bond
70lb quad crown 480 361/2lb double crown 24lb demy 85gsm 223/4lb bond
70lb quad crown 516 34lb double crown 221/4lb demy 79gsm 211/4lb bond
72lb quad crown 500 36lb double crown 233/4lb demy 84gsm 221/2lb bond
72lb quad crown 504 353/4lb double crown 231/2lb demy 84gsm 221/4lb bond
80lb quad crown 500 40lb double crown 261/4lb demy 94gsm 25lb bond
80lb quad crown 504 393/4lb double crown 26lb demy 93gsm 243/4lb bond
80lb quad crown 516 383/4lb double crown 251/2lb demy 91gsm 241/4lb bond
86lb quad crown 480 443/4lb double crown 291/2lb demy 105gsm 28lb bond
88lb quad crown 500 44lb double crown 29lb demy 103gsm 271/2lb bond
96lb quad crown 516 461/2lb double crown 301/2lb demy 109gsm 29lb bond
100lb quad crown 500 50lb double crown 323/4lb demy 117gsm 311/4lb bond
100lb quad crown 504 491/2lb double crown 321/2lb demy 116gsm 31lb bond
100lb quad crown 516 481/2lb double crown 313/4lb demy 114gsm 301/4lb bond
120lb quad crown 500 60lb double crown 391/2lb demy 141gsm 371/2lb bond
120lb quad crown 504 591/2lb double crown 39lb demy 139gsm 37lb bond
120lb quad crown 516 581/4lb double crown 381/4lb demy 136gsm 361/4lb bond
14lb demy 480 221/4lb double crown 141/2lb demy 52gsm 133/4lb bond
16lb demy 480 251/2lb double crown 163/4lb demy 60gsm 153/4lb bond
17lb demy 480 27lb double crown 173/4lb demy 63gsm 163/4lb bond
18lb demy 480 281/2lb double crown 183/4lb demy 67gsm 173/4lb bond
18lb demy 504 271/4lb double crown 173/4lb demy 64gsm 17lb bond
19lb demy 480 301/4lb double crown 193/4lb demy 71gsm 183/4lb bond
20lb demy 480 313/4lb double crown 203/4lb demy 74gsm 193/4lb bond
20lb demy 504 301/4lb double crown 193/4lb demy 71gsm 183/4lb bond
20lb demy 516 291/2lb double crown 191/2lb demy 69gsm 181/2lb bond
21lb demy 480 331/4lb double crown 22lb demy 78gsm 203/4lb bond
24lb demy 504 361/4lb double crown 233/4lb demy 85gsm 221/2lb bond
25lb demy 480 393/4lb double crown 26lb demy 93gsm 243/4lb bond
26lb demy 480 411/4lb double crown 27lb demy 97gsm 253/4lb bond
28lb demy 480 441/2lb double crown 291/4lb demy 104gsm 273/4lb bond
29lb demy 480 46lb double crown 301/4lb demy 108gsm 283/4lb bond
30lb demy 480 471/2lb double crown 311/4lb demy 112gsm 293/4lb bond
30lb demy 516 441/4lb double crown 29lb demy 104gsm 271/2lb bond
32lb demy 480 503/4lb double crown 331/4lb demy 119gsm 313/4lb bond
34lb demy 480 54lb double crown 351/2lb demy 126gsm 333/4lb bond
35lb demy 480 551/2lb double crown 361/2lb demy 130gsm 341/2lb bond
36lb demy 480 571/4lb double crown 371/2lb demy 134gsm 351/2lb bond
44lb demy 480 693/4lb double crown 453/4lb demy 164gsm 431/2lb bond
64lb demy 516 941/2lb double crown 62lb demy 221gsm 59lb bond
23lb double demy 480 181/4lb double crown 12lb demy 43gsm 111/2lb bond
25lb double demy 480 193/4lb double crown 13lb demy 46gsm 121/4lb bond
26lb double demy 480 203/4lb double crown 131/2lb demy 48gsm 123/4lb bond
28lb double demy 480 221/4lb double crown 141/2lb demy 52gsm 133/4lb bond
28lb double demy 516 203/4lb double crown 131/2lb demy 48gsm 13lb bond
30lb double demy 480 233/4lb double crown 153/4lb demy 56gsm 143/4lb bond
30lb double demy 516 221/4lb double crown 141/2lb demy 52gsm 133/4lb bond
32lb double demy 480 251/2lb double crown 163/4lb demy 60gsm 153/4lb bond
32lb double demy 504 241/4lb double crown 153/4lb demy 57gsm 15lb bond
32lb double demy 516 231/2lb double crown 151/2lb demy 55gsm 143/4lb bond
33lb double demy 480 261/4lb double crown 171/4lb demy 61gsm 161/4lb bond
34lb double demy 480 27lb double crown 173/4lb demy 63gsm 163/4lb bond
34lb double demy 504 253/4lb double crown 163/4lb demy 60gsm 16lb bond
34lb double demy 516 25lb double crown 161/2lb demy 59gsm 153/4lb bond
35lb double demy 480 273/4lb double crown 181/4lb demy 65gsm 171/4lb bond
36lb double demy 480 281/2lb double crown 183/4lb demy 67gsm 173/4lb bond
36lb double demy 500 271/2lb double crown 18lb demy 64gsm 17lb bond
36lb double demy 504 271/4lb double crown 173/4lb demy 64gsm 17lb bond
36lb double demy 516 261/2lb double crown 171/2lb demy 62gsm 161/2lb bond
38lb double demy 480 301/4lb double crown 193/4lb demy 71gsm 183/4lb bond
38lb double demy 504 283/4lb double crown 183/4lb demy 67gsm 18lb bond
40lb double demy 480 313/4lb double crown 203/4lb demy 74gsm 193/4lb bond
40lb double demy 500 301/2lb double crown 20lb demy 71gsm 19lb bond
40lb double demy 504 301/4lb double crown 193/4lb demy 71gsm 183/4lb bond
40lb double demy 516 291/2lb double crown 191/2lb demy 69gsm 181/2lb bond
42lb double demy 480 331/4lb double crown 22lb demy 78gsm 203/4lb bond
42lb double demy 516 31lb double crown 201/4lb demy 73gsm 191/4lb bond
44lb double demy 516 321/2lb double crown 211/4lb demy 76gsm 201/4lb bond
45lb double demy 500 341/4lb double crown 221/2lb demy 80gsm 211/4lb bond
45lb double demy 516 331/4lb double crown 213/4lb demy 78gsm 203/4lb bond
46lb double demy 480 361/2lb double crown 24lb demy 86gsm 223/4lb bond
46lb double demy 516 34lb double crown 221/4lb demy 80gsm 211/4lb bond
47lb double demy 516 343/4lb double crown 223/4lb demy 81gsm 211/2lb bond
48lb double demy 480 38lb double crown 25lb demy 89gsm 233/4lb bond
48lb double demy 500 361/2lb double crown 24lb demy 86gsm 223/4lb bond
48lb double demy 504 361/4lb double crown 233/4lb demy 85gsm 221/2lb bond
48lb double demy 516 351/2lb double crown 231/4lb demy 83gsm 22lb bond
50lb double demy 480 393/4lb double crown 26lb demy 93gsm 243/4lb bond
52lb double demy 504 391/4lb double crown 253/4lb demy 92gsm 241/2lb bond
53lb double demy 516 391/4lb double crown 253/4lb demy 92gsm 241/2lb bond
54lb double demy 480 423/4lb double crown 281/4lb demy 100gsm 263/4lb bond
55lb double demy 480 433/4lb double crown 283/4lb demy 102gsm 271/4lb bond
55lb double demy 516 401/2lb double crown 263/4lb demy 95gsm 251/4lb bond
56lb double demy 480 441/2lb double crown 291/4lb demy 104gsm 273/4lb bond
56lb double demy 516 411/4lb double crown 271/4lb demy 97gsm 253/4lb bond
60lb double demy 480 471/2lb double crown 311/4lb demy 112gsm 293/4lb bond
60lb double demy 504 451/4lb double crown 293/4lb demy 106gsm 281/4lb bond
60lb double demy 516 441/4lb double crown 29lb demy 104gsm 271/2lb bond
64lb double demy 516 471/4lb double crown 31lb demy 111gsm 291/2lb bond
68lb double demy 480 54lb double crown 351/2lb demy 126gsm 333/4lb bond
69lb double demy 480 543/4lb double crown 36lb demy 128gsm 341/4lb bond
70lb double demy 480 551/2lb double crown 361/2lb demy 130gsm 341/2lb bond
72lb double demy 516 531/4lb double crown 35lb demy 125gsm 331/4lb bond
74lb double demy 480 583/4lb double crown 381/2lb demy 138gsm 361/2lb bond
80lb double demy 504 601/2lb double crown 393/4lb demy 142gsm 373/4lb bond
88lb double demy 516 65lb double crown 423/4lb demy 152gsm 401/2lb bond
89lb double demy 480 703/4lb double crown 461/4lb demy 166gsm 44lb bond
19lb medium 480 283/4lb double crown 183/4lb demy 67gsm 18lb bond
20lb medium 480 301/4lb double crown 193/4lb demy 71gsm 183/4lb bond
24lb medium 480 361/4lb double crown 233/4lb demy 85gsm 221/2lb bond
25lb medium 480 373/4lb double crown 243/4lb demy 88gsm 231/2lb bond
25lb medium 504 36lb double crown 231/2lb demy 84gsm 221/2lb bond
27lb medium 480 403/4lb double crown 263/4lb demy 96gsm 251/2lb bond
28lb medium 480 421/4lb double crown 273/4lb demy 99gsm 261/4lb bond
29lb medium 480 433/4lb double crown 283/4lb demy 103gsm 271/4lb bond
30lb medium 480 451/4lb double crown 293/4lb demy 106gsm 281/4lb bond
30lb medium 516 421/4lb double crown 273/4lb demy 99gsm 261/4lb bond
31lb medium 480 463/4lb double crown 303/4lb demy 110gsm 291/4lb bond
32lb medium 480 481/4lb double crown 313/4lb demy 113gsm 30lb bond
33lb medium 516 461/4lb double crown 301/2lb demy 109gsm 29lb bond
34lb medium 480 511/4lb double crown 333/4lb demy 120gsm 32lb bond
34lb medium 504 49lb double crown 32lb demy 115gsm 301/2lb bond
35lb medium 480 523/4lb double crown 343/4lb demy 124gsm 33lb bond
38lb medium 516 531/4lb double crown 35lb demy 125gsm 331/4lb bond
40lb medium 480 601/2lb double crown 393/4lb demy 142gsm 373/4lb bond
40lb medium 504 571/2lb double crown 373/4lb demy 135gsm 353/4lb bond
40lb medium 516 561/4lb double crown 363/4lb demy 132gsm 35lb bond
45lb medium 480 68lb double crown 441/2lb demy 159gsm 421/4lb bond
48lb medium 480 721/2lb double crown 471/2lb demy 170gsm 451/4lb bond
50lb medium 504 72lb double crown 471/4lb demy 168gsm 443/4lb bond
53lb medium 504 761/4lb double crown 50lb demy 179gsm 471/2lb bond
55lb medium 480 83lb double crown 541/2lb demy 195gsm 513/4lb bond
42lb double medium 480 313/4lb double crown 203/4lb demy 74gsm 193/4lb bond
50lb double medium 480 373/4lb double crown 243/4lb demy 88gsm 231/2lb bond
50lb double medium 504 36lb double crown 231/2lb demy 84gsm 221/2lb bond
50lb double medium 516 35lb double crown 23lb demy 82gsm 22lb bond
55lb double medium 500 393/4lb double crown 261/4lb demy 93gsm 243/4lb bond
60lb double medium 500 431/2lb double crown 281/2lb demy 102gsm 27lb bond
60lb double medium 516 421/4lb double crown 273/4lb demy 99gsm 261/4lb bond
62lb double medium 500 45lb double crown 291/2lb demy 105gsm 28lb bond
64lb double medium 516 45lb double crown 291/2lb demy 105gsm 28lb bond
65lb double medium 500 47lb double crown 31lb demy 110gsm 291/4lb bond
68lb double medium 480 511/4lb double crown 333/4lb demy 120gsm 32lb bond
68lb double medium 504 49lb double crown 32lb demy 115gsm 301/2lb bond
69lb double medium 500 50lb double crown 323/4lb demy 117gsm 311/4lb bond
70lb double medium 500 503/4lb double crown 331/4lb demy 119gsm 311/2lb bond
80lb double medium 500 58lb double crown 38lb demy 136gsm 361/4lb bond
80lb double medium 516 561/4lb double crown 363/4lb demy 132gsm 35lb bond
20lb royal 480 25lb double crown 161/2lb demy 59gsm 151/2lb bond
21lb royal 516 241/2lb double crown 16lb demy 57gsm 151/4lb bond
22lb royal 480 271/2lb double crown 18lb demy 64gsm 171/4lb bond
23lb royal 480 283/4lb double crown 183/4lb demy 67gsm 18lb bond
24lb royal 480 30lb double crown 193/4lb demy 70gsm 183/4lb bond
24lb royal 504 281/2lb double crown 183/4lb demy 67gsm 173/4lb bond
24lb royal 516 28lb double crown 181/4lb demy 65gsm 171/2lb bond
25lb royal 516 29lb double crown 19lb demy 68gsm 18lb bond
26lb royal 480 321/2lb double crown 211/4lb demy 76gsm 201/4lb bond
26lb royal 516 301/4lb double crown 193/4lb demy 71gsm 183/4lb bond
27lb royal 516 311/2lb double crown 201/2lb demy 74gsm 191/2lb bond
30lb royal 480 371/2lb double crown 241/2lb demy 88gsm 231/4lb bond
30lb royal 516 35lb double crown 23lb demy 82gsm 213/4lb bond
31lb royal 480 383/4lb double crown 251/2lb demy 91gsm 241/4lb bond
32lb royal 480 40lb double crown 261/4lb demy 94gsm 25lb bond
33lb royal 480 411/4lb double crown 27lb demy 97gsm 253/4lb bond
34lb royal 480 421/2lb double crown 28lb demy 100gsm 261/2lb bond
36lb royal 480 45lb double crown 291/2lb demy 105gsm 28lb bond
36lb royal 516 413/4lb double crown 271/2lb demy 98gsm 26lb bond
37lb royal 480 461/4lb double crown 301/4lb demy 108gsm 283/4lb bond
38lb royal 480 471/2lb double crown 311/4lb demy 111gsm 291/2lb bond
39lb royal 480 483/4lb double crown 32lb demy 114gsm 301/2lb bond
40lb royal 480 50lb double crown 323/4lb demy 117gsm 311/4lb bond
40lb royal 504 471/2lb double crown 311/4lb demy 112gsm 293/4lb bond
40lb royal 516 461/2lb double crown 301/2lb demy 109gsm 29lb bond
41lb royal 480 511/4lb double crown 333/4lb demy 120gsm 32lb bond
42lb royal 480 521/2lb double crown 341/2lb demy 123gsm 323/4lb bond
44lb royal 480 55lb double crown 36lb demy 129gsm 341/4lb bond
45lb royal 480 561/4lb double crown 37lb demy 132gsm 35lb bond
47lb royal 480 583/4lb double crown 381/2lb demy 138gsm 361/2lb bond
50lb royal 480 621/2lb double crown 41lb demy 146gsm 39lb bond
50lb royal 504 591/2lb double crown 39lb demy 139gsm 37lb bond
50lb royal 516 581/4lb double crown 381/4lb demy 136gsm 361/4lb bond
51lb royal 480 633/4lb double crown 413/4lb demy 149gsm 393/4lb bond
60lb royal 480 75lb double crown 491/4lb demy 176gsm 463/4lb bond
61lb royal 480 761/4lb double crown 50lb demy 179gsm 471/2lb bond
66lb royal 480 821/2lb double crown 541/4lb demy 193gsm 511/2lb bond
67lb royal 504 793/4lb double crown 521/4lb demy 187gsm 493/4lb bond
70lb royal 480 871/2lb double crown 571/2lb demy 205gsm 541/2lb bond
32lb double royal 500 191/4lb double crown 121/2lb demy 45gsm 12lb bond
37lb double royal 480 231/4lb double crown 151/4lb demy 54gsm 141/2lb bond
40lb double royal 504 233/4lb double crown 153/4lb demy 56gsm 143/4lb bond
42lb double royal 516 241/2lb double crown 16lb demy 57gsm 151/4lb bond
46lb double royal 480 283/4lb double crown 183/4lb demy 67gsm 18lb bond
48lb double royal 504 281/2lb double crown 183/4lb demy 67gsm 173/4lb bond
48lb double royal 516 28lb double crown 181/4lb demy 65gsm 171/2lb bond
50lb double royal 500 30lb double crown 193/4lb demy 70gsm 183/4lb bond
50lb double royal 516 29lb double crown 19lb demy 68gsm 18lb bond
54lb double royal 516 311/2lb double crown 201/2lb demy 74gsm 191/2lb bond
60lb double royal 500 36lb double crown 233/4lb demy 84gsm 221/2lb bond
60lb double royal 504 353/4lb double crown 231/2lb demy 84gsm 221/4lb bond
60lb double royal 516 35lb double crown 23lb demy 82gsm 213/4lb bond
661/2lb double royal 500 40lb double crown 261/4lb demy 94gsm 243/4lb bond
72lb double royal 504 423/4lb double crown 281/4lb demy 100gsm 263/4lb bond
72lb double royal 516 413/4lb double crown 271/2lb demy 98gsm 26lb bond
75lb double royal 500 45lb double crown 291/2lb demy 105gsm 28lb bond
80lb double royal 504 471/2lb double crown 311/4lb demy 112gsm 293/4lb bond
80lb double royal 516 461/2lb double crown 301/2lb demy 109gsm 29lb bond
91lb double royal 516 53lb double crown 343/4lb demy 124gsm 33lb bond
100lb double royal 504 591/2lb double crown 39lb demy 139gsm 37lb bond
100lb double royal 516 581/4lb double crown 381/4lb demy 136gsm 361/4lb bond
160lb quad royal 504 471/2lb double crown 311/4lb demy 112gsm 293/4lb bond
16lb crown 480 331/4lb double crown 22lb demy 78gsm 203/4lb bond
20lb crown 480 413/4lb double crown 271/4lb demy 98gsm 26lb bond
27lb crown 480 561/4lb double crown 37lb demy 132gsm 35lb bond
16lb double foolscap 480 213/4lb double crown 141/4lb demy 51gsm 131/2lb bond
21lb double foolscap 480 281/2lb double crown 183/4lb demy 67gsm 173/4lb bond
22lb double foolscap 480 30lb double crown 193/4lb demy 70gsm 183/4lb bond
23lb double foolscap 516 291/4lb double crown 19lb demy 68gsm 181/4lb bond
24lb double foolscap 480 323/4lb double crown 211/2lb demy 77gsm 201/4lb bond
25lb double foolscap 516 313/4lb double crown 203/4lb demy 74gsm 193/4lb bond
26lb double foolscap 480 351/2lb double crown 231/4lb demy 83gsm 22lb bond
28lb double foolscap 480 381/4lb double crown 25lb demy 89gsm 233/4lb bond
28lb double foolscap 516 351/2lb double crown 231/4lb demy 83gsm 22lb bond
29lb double foolscap 480 391/2lb double crown 26lb demy 93gsm 241/2lb bond
30lb double foolscap 480 403/4lb double crown 263/4lb demy 96gsm 251/2lb bond
30lb double foolscap 516 38lb double crown 25lb demy 89gsm 233/4lb bond
32lb double foolscap 480 431/2lb double crown 281/2lb demy 102gsm 271/4lb bond
36lb double foolscap 480 49lb double crown 321/4lb demy 115gsm 301/2lb bond
36lb double foolscap 516 451/2lb double crown 30lb demy 107gsm 281/2lb bond
38lb double foolscap 480 513/4lb double crown 34lb demy 121gsm 321/4lb bond
40lb double foolscap 480 541/2lb double crown 353/4lb demy 128gsm 34lb bond
45lb double foolscap 480 611/4lb double crown 401/4lb demy 144gsm 381/4lb bond
54lb double foolscap 480 731/2lb double crown 481/4lb demy 172gsm 453/4lb bond
67lb double foolscap 480 911/4lb double crown 593/4lb demy 214gsm 563/4lb bond
46lb quad foolscap 516 291/4lb double crown 19lb demy 68gsm 181/4lb bond
48lb quad foolscap 504 31lb double crown 201/2lb demy 73gsm 191/2lb bond
49lb quad foolscap 516 31lb double crown 201/4lb demy 73gsm 191/4lb bond
50lb quad foolscap 516 313/4lb double crown 203/4lb demy 74gsm 193/4lb bond
56lb quad foolscap 504 361/4lb double crown 233/4lb demy 85gsm 223/4lb bond
56lb quad foolscap 516 351/2lb double crown 231/4lb demy 83gsm 22lb bond
60lb quad foolscap 504 39lb double crown 251/2lb demy 91gsm 241/4lb bond
60lb quad foolscap 516 38lb double crown 25lb demy 89gsm 233/4lb bond
68lb quad foolscap 480 461/4lb double crown 301/2lb demy 108gsm 283/4lb bond
64lb quad demy 516 231/2lb double crown 151/2lb demy 55gsm 143/4lb bond
80lb quad demy 516 291/2lb double crown 191/2lb demy 69gsm 181/2lb bond
84lb quad demy 516 31lb double crown 201/4lb demy 73gsm 191/4lb bond
96lb quad demy 504 361/4lb double crown 233/4lb demy 85gsm 221/2lb bond
120lb quad demy 504 451/4lb double crown 293/4lb demy 106gsm 281/4lb bond
120lb quad demy 516 441/4lb double crown 29lb demy 104gsm 271/2lb bond
30lb imperial (writing and printing) 516 261/2lb double crown 171/4lb demy 62gsm 161/2lb bond
36lb imperial (writing and printing) 516 313/4lb double crown 203/4lb demy 74gsm 193/4lb bond
40lb imperial (writing and printing) 516 351/4lb double crown 23lb demy 83gsm 22lb bond
46lb imperial (writing and printing) 480 431/2lb double crown 281/2lb demy 102gsm 271/4lb bond
50lb imperial (writing and printing) 516 44lb double crown 29lb demy 103gsm 271/2lb bond
56lb imperial (writing and printing) 480 53lb double crown 343/4lb demy 124gsm 33lb bond
60lb imperial (writing and printing) 516 523/4lb double crown 343/4lb demy 124gsm 33lb bond
70lb imperial (writing and printing) 480 661/4lb double crown 431/2lb demy 155gsm 411/4lb bond
120lb imperial (writing and printing) 516 1053/4lb double crown 691/4lb demy 248gsm 653/4lb bond
13lb post (printing) (pre–⁠1937 standardisation) 480 271/4lb double crown 18lb demy 64gsm 17lb bond
14lb post (printing) (pre–⁠1937 standardisation) 480 291/4lb double crown 191/4lb demy 69gsm 181/4lb bond
22lb post (printing) (pre–⁠1937 standardisation) 480 46lb double crown 301/4lb demy 108gsm 283/4lb bond
23lb post (printing) (pre–⁠1937 standardisation) 480 481/4lb double crown 311/2lb demy 113gsm 30lb bond
24lb post (printing) (pre–⁠1937 standardisation) 480 501/4lb double crown 33lb demy 118gsm 311/4lb bond
16lb large post 480 283/4lb double crown 19lb demy 68gsm 18lb bond
17lb large post 480 303/4lb double crown 20lb demy 72gsm 19lb bond
18lb large post 480 321/2lb double crown 211/4lb demy 76gsm 201/4lb bond
18lb large post 500 311/4lb double crown 201/2lb demy 73gsm 191/2lb bond
21lb large post 480 38lb double crown 243/4lb demy 89gsm 231/2lb bond
21lb large post 500 361/4lb double crown 233/4lb demy 85gsm 223/4lb bond
21lb large post 504 36lb double crown 233/4lb demy 85gsm 221/2lb bond
24lb large post 480 431/4lb double crown 281/2lb demy 101gsm 27lb bond
25lb large post 480 45lb double crown 291/2lb demy 106gsm 28lb bond
26lb large post 480 47lb double crown 303/4lb demy 110gsm 291/4lb bond
27lb large post 480 483/4lb double crown 32lb demy 114gsm 301/4lb bond
28lb large post 480 501/2lb double crown 33lb demy 118gsm 311/2lb bond
29lb large post 480 521/4lb double crown 341/4lb demy 123gsm 321/2lb bond
30lb large post 480 54lb double crown 351/2lb demy 127gsm 333/4lb bond
30lb large post 504 511/2lb double crown 333/4lb demy 121gsm 32lb bond
31lb large post 480 56lb double crown 363/4lb demy 131gsm 343/4lb bond
32lb large post 480 573/4lb double crown 38lb demy 135gsm 36lb bond
34lb large post 480 611/4lb double crown 401/4lb demy 144gsm 381/4lb bond
36lb large post 480 65lb double crown 421/2lb demy 152gsm 401/2lb bond
44lb large post 480 791/4lb double crown 52lb demy 186gsm 491/2lb bond
36lb double large post 516 301/4lb double crown 193/4lb demy 71gsm 183/4lb bond
60lb double large post 480 54lb double crown 351/2lb demy 127gsm 333/4lb bond
60lb double large post 504 511/2lb double crown 333/4lb demy 121gsm 32lb bond
20lb 121/2″-by-19″ 480 521/2lb double crown 341/2lb demy 123gsm 323/4lb bond
25lb 15″-by-221/2″ 480 461/4lb double crown 301/4lb demy 108gsm 283/4lb bond
25lb 15″-by-23″ 480 451/4lb double crown 293/4lb demy 106gsm 281/4lb bond
20lb 151/2″-by-18″ 480 443/4lb double crown 291/2lb demy 105gsm 28lb bond
25lb 17″-by-23″ 480 40lb double crown 261/4lb demy 94gsm 25lb bond
30lb 17″-by-23″ 480 48lb double crown 311/2lb demy 112gsm 30lb bond
67lb 201/2″-by-251/2″ 500 77lb double crown 501/2lb demy 180gsm 48lb bond
84lb 201/2″-by-251/2″ 500 961/2lb double crown 631/4lb demy 226gsm 60lb bond
100lb 201/2″-by-251/2″ 500 1143/4lb double crown 751/4lb demy 269gsm 711/2lb bond
118lb 201/2″-by-251/2″ 500 1351/2lb double crown 883/4lb demy 317gsm 841/2lb bond
80lb 201/2″-by-301/2″ 500 763/4lb double crown 501/4lb demy 180gsm 473/4lb bond
100lb 201/2″-by-301/2″ 500 96lb double crown 63lb demy 225gsm 593/4lb bond
120lb 201/2″-by-301/2″ 500 1151/4lb double crown 751/2lb demy 270gsm 713/4lb bond
140lb 201/2″-by-301/2″ 500 1341/4lb double crown 881/4lb demy 315gsm 833/4lb bond
36lb 21″-by-29″ 516 341/4lb double crown 221/2lb demy 81gsm 211/2lb bond
75lb 21″-by-301/2″ 504 693/4lb double crown 453/4lb demy 163gsm 431/2lb bond
106lb 22″-by-25″ 500 1153/4lb double crown 753/4lb demy 271gsm 72lb bond
124lb 22″-by-25″ 500 1351/4lb double crown 883/4lb demy 317gsm 841/4lb bond
190lb 22″-by-25″ 500 2071/4lb double crown 136lb demy 486gsm 1291/4lb bond
122lb 22″-by-29″ 500 1143/4lb double crown 751/4lb demy 269gsm 711/2lb bond
144lb 22″-by-29″ 500 1351/2lb double crown 883/4lb demy 317gsm 841/2lb bond
220lb 22″-by-29″ 500 207lb double crown 1353/4lb demy 485gsm 129lb bond
Wrapping paper
Common British basis weights

(various paper sizes and ream sizes)

Equivalent weight of a 500‑sheet ream of double imperial paper, a British wrapping paper commonly used to express the basis weight of wrapping paper

(rounded to the nearest quarter)

(a common British basis for intra‑category comparison)

Equivalent weight of a 500‑sheet ream of demy paper, a British uncut printing paper commonly used by default to express the basis weight of different types of paper[a]

(rounded to the nearest quarter)

(a common British basis for cross‑category comparison)

Equivalent grammage

(rounded to the nearest one)

Equivalent weight of a 500‑sheet ream of bond paper, an American uncut paper commonly used to express the basis weight of paper

(rounded to the nearest quarter)

(a common American basis for cross‑category comparison)

28lb bag cap (pre–⁠1937 standardisation) 480 811/4lb double imperial (wrapping) 241/2lb demy 88gsm 231/4lb bond
40lb bag cap (pre–⁠1937 standardisation) 480 1161/4lb double imperial (wrapping) 35lb demy 125gsm 331/4lb bond
50lb casing 480 41lb double imperial (wrapping) 121/2lb demy 44gsm 113/4lb bond
60lb casing 480 491/4lb double imperial (wrapping) 143/4lb demy 53gsm 14lb bond
70lb casing 480 571/2lb double imperial (wrapping) 171/4lb demy 62gsm 161/2lb bond
80lb casing 480 653/4lb double imperial (wrapping) 193/4lb demy 71gsm 183/4lb bond
100lb casing 480 82lb double imperial (wrapping) 243/4lb demy 88gsm 231/2lb bond
120lb casing 480 981/2lb double imperial (wrapping) 293/4lb demy 106gsm 281/4lb bond
140lb casing 480 115lb double imperial (wrapping) 343/4lb demy 124gsm 33lb bond
160lb casing 480 1311/4lb double imperial (wrapping) 393/4lb demy 142gsm 373/4lb bond
13lb double crown 480 291/2lb double imperial (wrapping) 9lb demy 32gsm 81/2lb bond
15lb double crown 480 34lb double imperial (wrapping) 101/4lb demy 37gsm 93/4lb bond
19lb double crown 480 43lb double imperial (wrapping) 13lb demy 46gsm 121/4lb bond
23lb double crown 480 52lb double imperial (wrapping) 153/4lb demy 56gsm 15lb bond
24lb double crown 480 541/2lb double imperial (wrapping) 161/2lb demy 59gsm 151/2lb bond
47lb double crown 480 1061/2lb double imperial (wrapping) 32lb demy 115gsm 301/2lb bond
80lb double crown 480 1811/4lb double imperial (wrapping) 543/4lb demy 195gsm 52lb bond
100lb double crown 480 2261/2lb double imperial (wrapping) 681/4lb demy 244gsm 65lb bond
120lb double crown 480 272lb double imperial (wrapping) 82lb demy 293gsm 78lb bond
34lb quad crown 480 381/2lb double imperial (wrapping) 111/2lb demy 42gsm 11lb bond
38lb quad crown 480 43lb double imperial (wrapping) 13lb demy 46gsm 121/4lb bond
48lb quad crown 504 513/4lb double imperial (wrapping) 151/2lb demy 56gsm 143/4lb bond
120lb quad crown 516 1261/2lb double imperial (wrapping) 381/4lb demy 136gsm 361/4lb bond
15lb demy 480 513/4lb double imperial (wrapping) 153/4lb demy 56gsm 143/4lb bond
26lb double demy 480 45lb double imperial (wrapping) 131/2lb demy 48gsm 123/4lb bond
29lb double demy 516 461/2lb double imperial (wrapping) 14lb demy 50gsm 131/4lb bond
30lb double demy 480 513/4lb double imperial (wrapping) 153/4lb demy 56gsm 143/4lb bond
34lb double demy 480 583/4lb double imperial (wrapping) 173/4lb demy 63gsm 163/4lb bond
60lb double demy 480 1031/2lb double imperial (wrapping) 311/4lb demy 112gsm 293/4lb bond
200lb extra large casing 480 1411/2lb double imperial (wrapping) 423/4lb demy 153gsm 401/2lb bond
50lb imperial (wrapping) 480 1041/4lb double imperial (wrapping) 311/2lb demy 112gsm 293/4lb bond
60lb imperial (wrapping) 480 125lb double imperial (wrapping) 373/4lb demy 135gsm 353/4lb bond
70lb imperial (wrapping) 480 1453/4lb double imperial (wrapping) 44lb demy 157gsm 413/4lb bond
140lb imperial (wrapping) 480 2913/4lb double imperial (wrapping) 88lb demy 314gsm 831/2lb bond
60lb double imperial (wrapping) 480 621/2lb double imperial (wrapping) 183/4lb demy 67gsm 18lb bond
65lb double imperial (wrapping) 480 673/4lb double imperial (wrapping) 201/2lb demy 73gsm 191/2lb bond
80lb double imperial (wrapping) 480 831/4lb double imperial (wrapping) 251/4lb demy 90gsm 24lb bond
100lb double imperial (wrapping) 480 1041/4lb double imperial (wrapping) 311/2lb demy 112gsm 293/4lb bond
120lb double imperial (wrapping) 480 125lb double imperial (wrapping) 373/4lb demy 135gsm 353/4lb bond
140lb double imperial (wrapping) 480 1453/4lb double imperial (wrapping) 44lb demy 157gsm 413/4lb bond
160lb double imperial (wrapping) 480 1663/4lb double imperial (wrapping) 501/4lb demy 180gsm 473/4lb bond
240lb double imperial (wrapping) 480 250lb double imperial (wrapping) 751/2lb demy 269gsm 713/4lb bond
240lb double double imperial 480 125lb double imperial (wrapping) 373/4lb demy 135gsm 353/4lb bond
280lb double double imperial 480 1453/4lb double imperial (wrapping) 44lb demy 157gsm 413/4lb bond
19lb small royal 480 563/4lb double imperial (wrapping) 17lb demy 61gsm 161/4lb bond
34lb quad small hand 480 381/2lb double imperial (wrapping) 111/2lb demy 42gsm 11lb bond
38lb quad small hand 480 43lb double imperial (wrapping) 13lb demy 46gsm 121/4lb bond
48lb quad small hand 504 513/4lb double imperial (wrapping) 151/2lb demy 56gsm 143/4lb bond
14lb 18″-by-26″ 480 403/4lb double imperial (wrapping) 121/4lb demy 44gsm 113/4lb bond
15lb 18″-by-26″ 480 431/2lb double imperial (wrapping) 131/4lb demy 47gsm 121/2lb bond
190lb 22″-by-25″ 500 4503/4lb double imperial (wrapping) 136lb demy 486gsm 1291/4lb bond
220lb 22″-by-29″ 500 450lb double imperial (wrapping) 1353/4lb demy 485gsm 129lb bond
32lb 251/2″-by-35″ 480 483/4lb double imperial (wrapping) 143/4lb demy 53gsm 14lb bond
26lb 30″-by-38″ 480 31lb double imperial (wrapping) 91/4lb demy 33gsm 83/4lb bond
30lb 30″-by-38″ 480 353/4lb double imperial (wrapping) 103/4lb demy 39gsm 101/4lb bond
42lb 30″-by-38″ 480 50lb double imperial (wrapping) 15lb demy 54gsm 141/4lb bond
180lb 38″-by-48″ 480 1341/4lb double imperial (wrapping) 401/2lb demy 145gsm 381/2lb bond

Conversion between British basis weights, American basis weights, and grammage

[edit]

It is possible to convert between different basis weights – both British and American – and grammage using different conversion formulae.

To convert between the basis weights of different paper with the same basis‑ream size (e. g., from lb large post 500 to lb demy 500), the following formula can be employed:[13]

Area of one sheet of paper in the target ream × Weight of the source ream ÷ Area of one sheet of paper in the source ream

To convert between the basis weights of different paper with different basis‑ream sizes (e. g., from lb large post 480 to lb demy 500), the relevant formula is below:

(Number of sheets of paper in the target ream × Area of one sheet of paper in the target ream) × Weight of the source ream ÷ (Number of sheets of paper in the source ream × Area of one sheet of paper in the source ream)[b]

To convert between the basis weights of the same paper with different basis‑ream sizes (e. g., from lb large post 480 to lb large post 500), one can either use the previous formula or the one below:

Weight of the source ream × Applicable conversion factor from the table below[14]

To convert to 480 500 504 516
480 1·042 1·05 1·075
500 0·96 1·01 1·032
504 0·95 0·992 1·022
516 0·93 0·969 0·977

To convert from a basis weight to its equivalent grammage, the following is the applicable formula:[15]

Weight of the basis ream × 703,125 ÷ Area of one sheet of paper in the basis ream in square inch × Number of sheets of paper in the basis ream

To convert from grammage to the equivalent basis weight, the formula below can be used:[15]

Area of one sheet of paper in the basis ream in square inch × Number of sheets of paper in the basis ream × Value of gram per square metre ÷ 703,125

Utilising the aforementioned formulae, it is possible to work out the conversion factors for converting between various British and American units of basis weight and the gram per square metre:

Table of conversion factors for British units of basis weight (standardised basis sizes and 500‑sheet basis reams only) and their metric and American equivalents
Note 1:
Value of lb demy × Relevant conversion factor = Value of the unit in the left column

Note 2:
Value of a unit in the left column ÷ Relevant conversion factor = Value of lb demy

Note 3:
To convert between any two units in the left column, Value of the source unit × (Conversion factor for the target unit ÷ Conversion factor for the source unit)

Note 4:
Note that, as a matter of mathematical relationship, 1 ‘single’ unit (e. g., lb foolscap) is always equal to 2 ‘double’ unit (e. g., lb double foolscap) and 4 ‘quad’ unit (e. g., lb quad foolscap), respectively. By the same token, 1 ‘double’ unit is always equal to 1/2 ‘single’ unit and 2 ‘quad’ unit, respectively; and 1 ‘quad’ unit is always equal to 1/2 ‘double’ unit and 1/4 ‘single’ unit, respectively. Due to the rounding of the conversion factors in this table, calculating with the conversion factors alone may not produce such results automatically.

lb demy (UK)
lb bag cap (UK) 1·219047
lb casing (the definition on the island of Great Britain) (UK) 4·205713
lb casing (the definition on the island of Ireland) (UK) 4·388570
lb double crown (UK) 1·523809
lb double demy (UK) 2
lb double double imperial (UK) 6·628570
lb double elephant (UK) 2·742856
lb double foolscap (UK) 1·165714
lb double imperial (writing and printing) (UK) 3·352380
lb double imperial (wrapping) (UK) 3·314285
lb double large post (UK) 1·759999
lb double medium (UK) 2·102856
lb double post (UK) 1·447619
lb double royal (UK) 2·539681
lb double small demy (UK) 1·574603
lb double small foolscap (UK) 1·110475
lb extra large casing (UK) 4·876188
lb foolscap (UK) 0·582857
lb imperial (writing and printing) (UK) 1·676190
lb imperial (wrapping) (UK) 1·657142
lb large post (UK) 0·880000
lb large royal (UK) 1·405713
lb medium (UK) 1·051428
lb post (UK) 0·723809
lb quad crown (UK) 3·047619
lb quad demy (UK) 4
lb quad foolscap (UK) 2·331429
lb royal (UK) 1·269840
lb saddleback (UK) 4·114285
lb sheet‑and‑a‑half small foolscap (UK) 0·832857
lb sheet‑and‑a‑third small foolscap (UK) 0·740317
lb small demy (UK) 0·787301
lb small foolscap (UK) 0·555237
lb small royal (UK) 1·158094
gsm (metric) 3·571142
lb bond (US) 0·949841
lb Bristol (US) 1·628571
lb cover (US) 1·320634
lb index (US) 1·975236
lb tag (US) 2·194284
lb text (US) 2·412696
Table of conversion factors for British units of basis weight (all basis sizes and basis‑ream sizes) and their metric and American equivalents
Note 1:
Value of lb demy 500 × Relevant conversion factor = Value of the unit in the left column

Note 2:
Value of a unit in the left column ÷ Relevant conversion factor = Value of lb demy 500

Note 3:
To convert between any two units in the left column, Value of the source unit × (Conversion factor for the target unit ÷ Conversion factor for the source unit)

Note 4:
Note that, as a matter of mathematical relationship, as long as the ream size is the same, 1 ‘single’ unit (e. g., lb crown 500) is always equal to 2 ‘double’ unit (e. g., lb double crown 500) and 4 ‘quad’ unit (e. g., lb quad crown 500), respectively. By the same token, 1 ‘double’ unit is always equal to 1/2 ‘single’ unit and 2 ‘quad’ unit, respectively; and 1 ‘quad’ unit is always equal to 1/2 ‘double’ unit and 1/4 ‘single’ unit, respectively. Due to the rounding of the conversion factors in this table, calculating with the conversion factors alone may not produce such results automatically.

lb demy 500 (UK)
lb atlas 480 (UK) 2·155275
lb atlas 500 (UK) 2·245079
lb atlas 504 (UK) 2·263039
lb atlas 516 (UK) 2·316921
lb bag cap 480 (the pre–‍1937 standardisation definition) (UK) 1·141027
lb bag cap 500 (the pre–‍1937 standardisation definition) (UK) 1·188571
lb bag cap 504 (the pre–‍1937 standardisation definition) (UK) 1·198079
lb bag cap 516 (the pre–‍1937 standardisation definition) (UK) 1·226605
lb bag cap 480 (UK) 1·170285
lb bag cap 500 (UK) 1·219047
lb bag cap 504 (UK) 1·228799
lb bag cap 516 (UK) 1·258056
lb casing 480 (definition on the island of Great Britain) (UK) 4·037483
lb casing 500 (definition on the island of Great Britain) (UK) 4·205713
lb casing 504 (definition on the island of Great Britain) (UK) 4·239357
lb casing 516 (definition on the island of Great Britain) (UK) 4·340294
lb casing 480 (definition on the island of Ireland) (UK) 4·213026
lb casing 500 (definition on the island of Ireland) (UK) 4·388570
lb casing 504 (definition on the island of Ireland) (UK) 4·423677
lb casing 516 (definition on the island of Ireland) (UK) 4·529003
lb copy 480 (UK) 0·804571
lb copy 500 (UK) 0·838095
lb copy 504 (UK) 0·844799
lb copy 516 (UK) 0·864914
lb crown 480 (UK) 0·731428
lb crown 500 (UK) 0·761905
lb crown 504 (UK) 0·768000
lb crown 516 (UK) 0·786285
lb demy 480 (UK) 0·960000
lb demy 504 (UK) 1·008000
lb demy 516 (UK) 1·032000
lb double bag cap 480 (UK) 2·282055
lb double bag cap 500 (UK) 2·377142
lb double bag cap 504 (UK) 2·396159
lb double bag cap 516 (UK) 2·453210
lb double crown 480 (UK) 1·462856
lb double crown 500 (UK) 1·523809
lb double crown 504 (UK) 1·535999
lb double crown 516 (UK) 1·572571
lb double demy 480 (UK) 1·919999
lb double demy 500 (UK) 2
lb double demy 504 (UK) 2·015999
lb double demy 516 (UK) 2·063999
lb double double imperial 480 (UK) 6·363425
lb double double imperial 500 (UK) 6·628570
lb double double imperial 504 (UK) 6·681596
lb double double imperial 516 (UK) 6·840682
lb double elephant (writing and printing) 480 (UK) 2·633141
lb double elephant (writing and printing) 500 (UK) 2·742856
lb double elephant (writing and printing) 504 (UK) 2·764798
lb double elephant (writing and printing) 516 (UK) 2·830627
lb double elephant (wrapping) 480 (UK) 3·476721
lb double elephant (wrapping) 500 (UK) 3·621586
lb double elephant (wrapping) 504 (UK) 3·650557
lb double elephant (wrapping) 516 (UK) 3·737475
lb double foolscap 480 (UK) 1·119085
lb double foolscap 500 (UK) 1·165714
lb double foolscap 504 (UK) 1·175040
lb double foolscap 516 (UK) 1·203017
lb double globe 480 (UK) 2·594132
lb double globe 500 (UK) 2·702221
lb double globe 504 (UK) 2·723838
lb double globe 516 (UK) 2·788691
lb double imperial (writing and printing) 480 (UK) 3·218284
lb double imperial (writing and printing) 500 (UK) 3·352380
lb double imperial (writing and printing) 504 (UK) 3·379198
lb double imperial (writing and printing) 516 (UK) 3·459655
lb double imperial (wrapping) 480 (UK) 3·181712
lb double imperial (wrapping) 500 (UK) 3·314285
lb double imperial (wrapping) 504 (UK) 3·340798
lb double imperial (wrapping) 516 (UK) 3·420341
lb double large post 480 (UK) 1·689599
lb double large post 500 (UK) 1·759999
lb double large post 504 (UK) 1·774079
lb double large post 516 (UK) 1·816319
lb double medium 480 (UK) 2·018741
lb double medium 500 (UK) 2·102856
lb double medium 504 (UK) 2·119678
lb double medium 516 (UK) 2·170147
lb double post (writing) 480 (the pre–‍1937 standardisation definition) (UK) 1·412875
lb double post (writing) 500 (the pre–‍1937 standardisation definition) (UK) 1·471745
lb double post (writing) 504 (the pre–‍1937 standardisation definition) (UK) 1·483518
lb double post (writing) 516 (the pre–‍1937 standardisation definition) (UK) 1·518840
lb double post (printing) 480 (the pre–‍1937 standardisation definition) (UK) 1·454932
lb double post (printing) 500 (the pre–‍1937 standardisation definition) (UK) 1·515555
lb double post (printing) 504 (the pre–‍1937 standardisation definition) (UK) 1·527679
lb double post (printing) 516 (the pre–‍1937 standardisation definition) (UK) 1·564052
lb double post 480 (UK) 1·389714
lb double post 500 (UK) 1·447619
lb double post 504 (UK) 1·459199
lb double post 516 (UK) 1·493942
lb double pott 480 (UK) 0·914285
lb double pott 500 (UK) 0·952380
lb double pott 504 (UK) 0·959999
lb double pott 516 (UK) 0·982856
lb double royal 480 (UK) 2·438093
lb double royal 500 (UK) 2·539681
lb double royal 504 (UK) 2·559998
lb double royal 516 (UK) 2·620950
lb double small cap 480 (UK) 2·072379
lb double small cap 500 (UK) 2·158729
lb double small cap 504 (UK) 2·175998
lb double small cap 516 (UK) 2·227808
lb double small demy 480 (UK) 1·511618
lb double small demy 500 (UK) 1·574603
lb double small demy 504 (UK) 1·587199
lb double small demy 516 (UK) 1·624990
lb double small foolscap 480 (UK) 1·066056
lb double small foolscap 500 (UK) 1·110475
lb double small foolscap 504 (UK) 1·119359
lb double small foolscap 516 (UK) 1·146010
lb double small hand 480 (UK) 1·414095
lb double small hand 500 (UK) 1·473016
lb double small hand 504 (UK) 1·484799
lb double small hand 516 (UK) 1·520152
lb double small royal 480 (UK) 2·223541
lb double small royal 500 (UK) 2·316189
lb double small royal 504 (UK) 2·334718
lb double small royal 516 (UK) 2·620950
lb elephant (writing and printing) 480 (UK) 1·570132
lb elephant (writing and printing) 500 (UK) 1·635555
lb elephant (writing and printing) 504 (UK) 1·648639
lb elephant (writing and printing) 516 (UK) 1·687892
lb elephant (wrapping) 480 (UK) 1·872456
lb elephant (wrapping) 500 (UK) 1·950475
lb elephant (wrapping) 504 (UK) 1·966078
lb elephant (wrapping) 516 (UK) 2·012890
lb extra large casing 480 (UK) 4·681139
lb extra large casing 500 (UK) 4·876188
lb extra large casing 504 (UK) 4·915196
lb extra large casing 516 (UK) 5·032225
lb foolscap 480 (UK) 0·559543
lb foolscap 500 (UK) 0·582857
lb foolscap 504 (UK) 0·587520
lb foolscap 516 (UK) 0·601508
lb haven cap 480 (UK) 1·331199
lb haven cap 500 (UK) 1·386666
lb haven cap 504 (UK) 1·397759
lb haven cap 516 (UK) 1·431039
lb imperial (writing and printing) 480 (UK) 1·609142
lb imperial (writing and printing) 500 (UK) 1·676190
lb imperial (writing and printing) 504 (UK) 1·689599
lb imperial (writing and printing) 516 (UK) 1·729827
lb imperial (wrapping) 480 (UK) 1·590856
lb imperial (wrapping) 500 (UK) 1·657142
lb imperial (wrapping) 504 (UK) 1·670399
lb imperial (wrapping) 516 (UK) 1·710170
lb Kent cap 480 (UK) 0·959999
lb Kent cap 500 (UK) 0·999999
lb Kent cap 504 (UK) 1·007999
lb Kent cap 516 (UK) 1·031999
lb large post 480 (UK) 0·844799
lb large post 500 (UK) 0·880000
lb large post 504 (UK) 0·887039
lb large post 516 (UK) 0·908159
lb large royal 480 (the pre–‍1937 standardisation definition) (UK) 1·316571
lb large royal 500 (the pre–‍1937 standardisation definition) (UK) 1·371428
lb large royal 504 (the pre–‍1937 standardisation definition) (UK) 1·382399
lb large royal 516 (the pre–‍1937 standardisation definition) (UK) 1·415314
lb large royal 480 (UK) 1·349484
lb large royal 500 (UK) 1·405713
lb large royal 504 (UK) 1·416958
lb large royal 516 (UK) 1·450696
lb lumber hand 480 (UK) 0·960000
lb lumber hand 500 (UK) 1
lb lumber hand 504 (UK) 1·008000
lb lumber hand 516 (UK) 1·032000
lb medium 480 (UK) 1·009371
lb medium 500 (UK) 1·051428
lb medium 504 (UK) 1·059839
lb medium 516 (UK) 1·085073
lb music demy 480 (UK) 0·727238
lb music demy 500 (UK) 0·757540
lb music demy 504 (UK) 0·763600
lb music demy 516 (UK) 0·781781
lb pinched post 480 (UK) 0·665295
lb pinched post 500 (UK) 0·693016
lb pinched post 504 (UK) 0·698559
lb pinched post 516 (UK) 0·715192
lb post (writing) 480 (the pre–‍1925 standardisation definition) (UK) 0·706437
lb post (writing) 500 (the pre–‍1925 standardisation definition) (UK) 0·735872
lb post (writing) 504 (the pre–‍1925 standardisation definition) (UK) 0·741759
lb post (writing) 516 (the pre–‍1925 standardisation definition) (UK) 0·759420
lb post (printing) 480 (the pre–‍1925 standardisation definition) (UK) 0·727466
lb post (printing) 500 (the pre–‍1925 standardisation definition) (UK) 0·757777
lb post (printing) 504 (the pre–‍1925 standardisation definition) (UK) 0·763839
lb post (printing) 516 (the pre–‍1925 standardisation definition) (UK) 0·782026
lb post 480 (UK) 0·694857
lb post 500 (UK) 0·723809
lb post 504 (UK) 0·729600
lb post 516 (UK) 0·746971
lb pott 480 (UK) 0·457143
lb pott 500 (UK) 0·476191
lb pott 504 (UK) 0·480000
lb pott 516 (UK) 0·491429
lb quad crown 480 (UK) 2·925713
lb quad crown 500 (UK) 3·047619
lb quad crown 504 (UK) 3·071998
lb quad crown 516 (UK) 3·145141
lb quad demy 480 (UK) 3·839999
lb quad demy 500 (UK) 4
lb quad demy 504 (UK) 4·031999
lb quad demy 516 (UK) 4·127999
lb quad foolscap 480 (UK) 2·238171
lb quad foolscap 500 (UK) 2·331429
lb quad foolscap 504 (UK) 2·350080
lb quad foolscap 516 (UK) 2·406034
lb quad globe 480 (UK) 5·188263
lb quad globe 500 (UK) 5·404442
lb quad globe 504 (UK) 5·447676
lb quad globe 516 (UK) 5·577383
lb quad pott 480 (UK) 1·828572
lb quad pott 500 (UK) 1·904763
lb quad pott 504 (UK) 1·920000
lb quad pott 516 (UK) 1·965715
lb quad royal 480 (UK) 4·876186
lb quad royal 500 (UK) 5·079362
lb quad royal 504 (UK) 5·119995
lb quad royal 516 (UK) 5·241900
lb quad small hand 480 (UK) 2·925712
lb quad small hand 500 (UK) 3·047618
lb quad small hand 504 (UK) 3·071998
lb quad small hand 516 (UK) 3·145140
lb royal 480 (UK) 1·219046
lb royal 500 (UK) 1·269840
lb royal 504 (UK) 1·279999
lb royal 516 (UK) 1·310475
lb saddleback 480 (UK) 3·949712
lb saddleback 500 (UK) 4·114285
lb saddleback 504 (UK) 4·147198
lb saddleback 516 (UK) 4·245940
lb sheet‑and‑a‑half small foolscap 480 (the pre–‍1925 standardisation definition) (UK) 0·791466
lb sheet‑and‑a‑half small foolscap 500 (the pre–‍1925 standardisation definition) (UK) 0·824444
lb sheet‑and‑a‑half small foolscap 504 (the pre–‍1925 standardisation definition) (UK) 0·831040
lb sheet‑and‑a‑half small foolscap 516 (the pre–‍1925 standardisation definition) (UK) 0·850826
lb sheet‑and‑a‑half small foolscap 480 (UK) 0·799543
lb sheet‑and‑a‑half small foolscap 500 (UK) 0·832857
lb sheet‑and‑a‑half small foolscap 504 (UK) 0·839520
lb sheet‑and‑a‑half small foolscap 516 (UK) 0·859508
lb sheet‑and‑a‑third small foolscap 480 (UK) 0·710704
lb sheet‑and‑a‑third small foolscap 500 (UK) 0·740317
lb sheet‑and‑a‑third small foolscap 504 (UK) 0·746240
lb sheet‑and‑a‑third small foolscap 516 (UK) 0·764007
lb small cap 480 (UK) 1·036190
lb small cap 500 (UK) 1·079364
lb small cap 504 (UK) 1·087999
lb small cap 516 (UK) 1·113904
lb small demy 480 (UK) 0·755809
lb small demy 500 (UK) 0·787301
lb small demy 504 (UK) 0·793599
lb small demy 516 (UK) 0·812495
lb small foolscap 480 (UK) 0·533028
lb small foolscap 500 (UK) 0·555237
lb small foolscap 504 (UK) 0·559679
lb small foolscap 516 (UK) 0·573005
lb small hand 480 (UK) 0·731428
lb small hand 500 (UK) 0·761905
lb small hand 504 (UK) 0·768000
lb small hand 516 (UK) 0·786285
lb small medium 480 (UK) 0·938666
lb small medium 500 (UK) 0·977777
lb small medium 504 (UK) 0·985599
lb small medium 516 (UK) 1·009066
lb small post 480 (UK) 0·654018
lb small post 500 (UK) 0·681269
lb small post 504 (UK) 0·686719
lb small post 516 (UK) 0·703070
lb small royal 480 (UK) 1·111770
lb small royal 500 (UK) 1·158094
lb small royal 504 (UK) 1·167359
lb small royal 516 (UK) 1·195153
lb super royal (writing) 480 (the pre–‍1925 standardisation definition) (UK) 1·267199
lb super royal (writing) 500 (the pre–‍1925 standardisation definition) (UK) 1·319999
lb super royal (writing) 504 (the pre–‍1925 standardisation definition) (UK) 1·330559
lb super royal (writing) 516 (the pre–‍1925 standardisation definition) (UK) 1·362239
lb super royal (printing) 480 (the pre–‍1925 standardisation definition) (UK) 1·374475
lb super royal (printing) 500 (the pre–‍1925 standardisation definition) (UK) 1·431745
lb super royal (printing) 504 (the pre–‍1925 standardisation definition) (UK) 1·443199
lb super royal (printing) 516 (the pre–‍1925 standardisation definition) (UK) 1·477561
lb super royal 480 (UK) 1·250742
lb super royal 500 (UK) 1·302856
lb super royal 504 (UK) 1·313279
lb super royal 516 (UK) 1·344547
lb 20″‑by‑24″ 480 (UK) 1·170285
lb 20″‑by‑24″ 500 (UK) 1·219047
lb 20″‑by‑24″ 504 (UK) 1·228799
lb 20″‑by‑24″ 516 (UK) 1·258056
lb 20″‑by‑28″ 480 (UK) 1·365333
lb 20″‑by‑28″ 500 (UK) 1·422222
lb 20″‑by‑28″ 504 (UK) 1·433599
lb 20″‑by‑28″ 516 (UK) 1·467733
lb 21″‑by‑31″ 480 (UK) 1·587199
lb 21″‑by‑31″ 500 (UK) 1·653333
lb 21″‑by‑31″ 504 (UK) 1·666559
lb 21″‑by‑31″ 516 (UK) 1·706239
lb 21″‑by‑34″ 480 (UK) 1·740799
lb 21″‑by‑34″ 500 (UK) 1·813333
lb 21″‑by‑34″ 504 (UK) 1·827839
lb 21″‑by‑34″ 516 (UK) 1·871359
lb 22″‑by‑32″ 480 (UK) 1·716418
lb 22″‑by‑32″ 500 (UK) 1·787936
lb 22″‑by‑32″ 504 (UK) 1·802239
lb 22″‑by‑32″ 516 (UK) 1·845149
lb 22″‑by‑35″ 480 (UK) 1·877332
lb 22″‑by‑35″ 500 (UK) 1·955555
lb 22″‑by‑35″ 504 (UK) 1·971198
lb 22″‑by‑35″ 516 (UK) 2·018132
lb 23″‑by‑34″ 480 (UK) 1·906589
lb 23″‑by‑34″ 500 (UK) 1·986031
lb 23″‑by‑34″ 504 (UK) 2·001918
lb 23″‑by‑34″ 516 (UK) 2·049583
lb 24″‑by‑30″ 480 (UK) 1·755427
lb 24″‑by‑30″ 500 (UK) 1·828571
lb 24″‑by‑30″ 504 (UK) 1·843199
lb 24″‑by‑30″ 516 (UK) 1·887084
lb 24″‑by‑36″ 480 (UK) 2·106512
lb 24″‑by‑36″ 500 (UK) 2·194284
lb 24″‑by‑36″ 504 (UK) 2·211838
lb 24″‑by‑36″ 516 (UK) 2·264501
lb 24″‑by‑40″ 480 (UK) 2·340569
lb 24″‑by‑40″ 500 (UK) 2·438094
lb 24″‑by‑40″ 504 (UK) 2·457598
lb 24″‑by‑40″ 516 (UK) 2·516112
lb 26″‑by‑36″ 480 (UK) 2·282056
lb 26″‑by‑36″ 500 (UK) 2·377142
lb 26″‑by‑36″ 504 (UK) 2·396159
lb 26″‑by‑36″ 516 (UK) 2·453210
lb 28″‑by‑45″ 480 (UK) 3·071998
lb 28″‑by‑45″ 500 (UK) 3·199999
lb 28″‑by‑45″ 504 (UK) 3·225598
lb 28″‑by‑45″ 516 (UK) 3·302398
lb 29″‑by‑44″ 480 (UK) 3·111008
lb 29″‑by‑44″ 500 (UK) 3·240634
lb 29″‑by‑44″ 504 (UK) 3·266558
lb 29″‑by‑44″ 516 (UK) 3·344333
lb 30″‑by‑38″ 480 (UK) 2·779426
lb 30″‑by‑38″ 500 (UK) 2·895237
lb 30″‑by‑38″ 504 (UK) 2·918398
lb 30″‑by‑38″ 516 (UK) 2·987883
lb 30″‑by‑46″ 480 (UK) 3·364569
lb 30″‑by‑46″ 500 (UK) 3·504761
lb 30″‑by‑46″ 504 (UK) 3·532798
lb 30″‑by‑46″ 516 (UK) 3·616912
lb 34″‑by‑36″ 480 (UK) 2·984227
lb 34″‑by‑36″ 500 (UK) 3·108571
lb 34″‑by‑36″ 504 (UK) 3·133438
lb 34″‑by‑36″ 516 (UK) 3·208044
lb 36″‑by‑36″ 480 (UK) 3·159770
lb 36″‑by‑36″ 500 (UK) 3·291428
lb 36″‑by‑36″ 504 (UK) 3·317758
lb 36″‑by‑36″ 516 (UK) 3·396752
lb 36″‑by‑48″ 480 (UK) 4·213026
lb 36″‑by‑48″ 500 (UK) 4·388570
lb 36″‑by‑48″ 504 (UK) 4·423677
lb 36″‑by‑48″ 516 (UK) 4·529003
lb 38″‑by‑48″ 480 (UK) 4·447083
lb 38″‑by‑48″ 500 (UK) 4·632379
lb 38″‑by‑48″ 504 (UK) 4·669437
lb 38″‑by‑48″ 516 (UK) 4·780614
lb 45″‑by‑56″ 480 (UK) 6·143996
lb 45″‑by‑56″ 500 (UK) 6·399998
lb 45″‑by‑56″ 504 (UK) 6·451196
lb 45″‑by‑56″ 516 (UK) 6·604796
gsm (metric) 3·571142
lb bond (US) 0·949841
lb Bristol (US) 1·628571
lb cover (US) 1·320634
lb index (US) 1·975236
lb tag (US) 2·194284
lb text (US) 2·412696

Using British basis sizes and the 500‑sheet basis‑ream (a traditional British basis‑ream size that coincides with the modern standard definition of ‘ream’), and with the help of the aforementioned conversion formulae or conversion factors, it is possible to express the paper weights of different types of paper in everyday life using British units of basis weight: the typical photocopier paper that is used as all‑purpose paper is 171/4 or 193/4lb large post (70 or 80gsm);[16] personal and business letter paper, especially that with engraved letterheads, is typically 243/4–291/2lb large post (100–120gsm);[17] greetings cards are usually 851/4–1063/4lb double crown (200–250gsm);[18] newspaper paper is typically 15–231/2lb double crown (35–55gsm);[19] business cards are usually 128–1491/4lb double crown (300–350gsm);[19] two‑ply toilet rolls and paper kitchen towels are 73/4lb double crown (31gsm)[20] (both layers combined) and 17lb double crown (40gsm),[21] respectively; and the typical department‑store wrapping paper is commonly 461/2–65lb double imperial (50–70gsm).[22]  In the traditional British system, large post, double crown, and double imperial are common British basis sizes for writing paper, printing paper and other paper that is not writing or wrapping paper, and wrapping paper, respectively.  ‘500’ is omitted because it is clear from the context that a ‘ream’ is 500 sheets.

Caliper

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Paper thickness, or caliper, is a common measurement specified and required for certain printing applications. Since a paper's density is typically not directly known or specified, the thickness of any sheet of paper cannot be calculated by any method. Instead, it is measured and specified separately as its caliper. However, paper thickness for most typical business papers might be similar across comparable brands. If thickness is not specified for a paper in question, it must be either measured or guessed based on a comparable paper's specification.

Caliper is usually measured in micrometres (μm), or in the United States also in mils (1 mil = 11000 in = 25.4 μm). Commonly, 20-pound bond paper ranges between roughly 97 and 114 μm (0.0038 and 0.0045 in) in thickness.[23]

The paper density is calculated by dividing the grammage over the caliper, and is usually expressed in grams per cubic centimetre (g/cm3)[24] to cancel out the mathematical need for unit conversions between metres and micrometres (a conversion factor of 1,000,000).[citation needed]

See also

[edit]

Notes

[edit]
  1. ^ a b c The pound per ream of demy paper has been chosen as the common unit for comparing the basis weights of paper in all three categories in this table, since there is a tradition of using demy as the default paper size for basis weight: in the British paper industry, there was a device, called ‘demy scale’, that was used to measure the weights of paper samples in pound per ream of demy paper (480‑sheet, 500‑sheet, and 516‑sheet reams).
  2. ^ This formula and the previous formula are essentially the same, with the only difference being the inclusion of the numbers of sheets of paper in both the source ream and the target ream. Technically, the numbers of sheets of paper should also be included in the previous formula. However, since the numbers of sheets of paper in the two reams will be cancelled out if they are the same, they can be omitted in the previous formula.

References

[edit]
  1. ^ International Standard ISO 536: Paper and board – Determination of grammage. International Organization for Standardization, Geneva.
  2. ^ "ISO 536:2019". ISO. Retrieved 5 October 2022.
  3. ^ Page 11, January, 1968 edition, Highlight
  4. ^ Page 3, July, 1967 edition, Highlight
  5. ^ Page 3, October, 1967 edition, Highlight
  6. ^ Pages 136, 138, and 142, Paper and Its Uses (1919 edition)
  7. ^ Pages 148, 150, and 171–173, Paper and Its Uses (1939 edition)
  8. ^ Page 29, The Papermakers’ Pocket Book (1911)
  9. ^ Page 168, Paper and Its Uses (1939 edition)
  10. ^ a b Pages 171–173, Paper and Its Uses (1939 edition)
  11. ^ a b Based on the basis weights mentioned in the paper‑related advertisements and articles in the following newspapers and paper‑industry magazines published during the days when the British paper industry exlcusively used basis weights:
  12. ^ Pages 96 and 97, Paper and Its Uses (1919 edition)
  13. ^ Page 368, November–December, 1894 edition, The British Printer
  14. ^ Page 148, Paper and Its Uses (1919 edition)
  15. ^ a b Page 157, Paper and Its Uses (1939 edition)
  16. ^ GSM Paper: the Complete Guide
  17. ^ What is GSM Paper Weight?’, Solopress Blog
  18. ^ Understanding the Different gsm Weights for Card and Paper Supplies’, Mankey Monkey
  19. ^ a b Paper GSM Guide’, The Paperbox Limited
  20. ^ For example, Kleenex toilet paper sold at https://www.galleonsupplies.co.uk/cheap-toilet-rolls-c10/bulk-pack-toilet-tissue-2-ply-p118.
  21. ^ For example, the paper kitchen towel sold at https://www.amazon.co.uk/Pack-20-Centrefeed-Absorbent-Commercial/dp/B0CC6BS768.
  22. ^ For example, the wrapping paper sold at https://www.transpack.co.uk/gift-display/coloured-kraft-wrapping-paper and https://www.makkipak.co.uk/product/kraft-paper-rolls-70gsm/.
  23. ^ "Paper Comparisons". 22 October 2012. Archived from the original on 22 October 2012.
  24. ^ "ISO 534:2011(en) Paper and board — Determination of thickness, density and specific volume".
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