ISO Paper sizes and specifications

ISO Paper Standards - Technical Definition Standard paper sizes like ISO A4 are widely used all over the world today. In the ISO paper size system, the height-to-width ratio of all pages is the square root of two (1.4142 : 1). In other words, the width and the height of a page relate to each other like the side and the diagonal of a square. This aspect ratio is especially convenient for a paper size. If you put two such pages next to each other, or equivalently cut one parallel to its shorter side into two equal pieces, then the resulting page will have again the same width/height ratio. The ISO paper sizes are based on the metric system. The square-root-of-two ratio does not permit both the height and width of the pages to be nicely rounded metric lengths. Therefore, the area of the pages has been defined to have round metric values. As paper is usually specified in g/m², this simplifies calculation of the mass of a document if the format and number of pages are known. ISO 216 defines the A series of paper sizes based on these simple principles: The height divided by the width of all formats is the square root of two (1.4142). Format A0 has an area of one square meter. Format A1 is A0 cut into two equal pieces. In other words, the height of A1 is the width of A0 and the width of A1 is half the height of A0. All smaller A series formats are defined in the same way. If you cut format An parallel to its shorter side into two equal pieces of paper, these will have format A(n+1). The standardized height and width of the paper formats is a rounded number of millimeters. For applications where the ISO A series does not provide an adequate format, the B series has been introduced to cover a wider range of paper sizes. The C series of formats has been defined for envelopes. The width and height of a Bn format are the geometric mean between those of the An and the next larger A(n-1) format. For instance, B1 is the geometric mean between A1 and A0, that means the same magnification factor that scales A1 to B1 also scales B1 to A0. Similarly, the formats of the C series are the geometric mean between the A and B series formats with the same number. For example, an (unfolded) A4 size letter fits nicely into a C4 envelope, which in turn fits as nicely into a B4 envelope. If you fold this letter once to A5 format, then it will fit nicely into a C5 envelope. B and C formats naturally are also square-root-of-two formats. ISO Paper Sizes A series formats Size mm inches 4A0 1682 × 2378 66 1/4 × 93 5/8 2A0 1189 × 1682 46 3/4 × 66 1/4 A0 841 × 1189 33 × 46 3/4 A1 594 × 841 23 3/8 × 33 A2 420 × 594 16 1/2 × 23 3/8 A3 297 × 420 11 3/4 × 16 1/2 A4 210 × 297 8 1/4 × 11 3/4 A5 148 × 210 5 7/8 × 8 1/4 A6 105 × 148 4 1/8 × 5 7/8 A7 74 × 105 2 7/8 × 4 1/8 A8 52 × 74 2 × 2 7/8 A9 37 × 52 1 1/2 × 2 A10 26 × 37 1 × 1 1/2 B series formats Size mm inches B0 1000 × 1414 39 3/8 × 55 3/4 B1 707 × 1000 27 3/4 × 39 3/8 B2 500 × 707 19 3/4 × 27 3/4 B3 353 × 500 13 7/8 × 19 3/4 B4 250 × 353 9 7/8 × 13 7/8 B5 176 × 250 7 × 9 7/8 B6 125 × 176 4 7/8 × 7 B7 88 × 125 3 1/2 × 4 7/8 B8 62 × 88 2 1/2 × 3 1/2 B9 44 × 62 1 3/4 × 2 1/2 B10 31 × 44 1 1/4 × 1 3/4 C series formats Size mm inches C0 917 × 1297 36 × 51 C1 648 × 917 25 1/2 × 36 C2 458 × 648 18 × 25 1/2 C3 324 × 458 12 3/4 × 18 C4 229 × 324 9 × 12 3/4 C5 162 × 229 6 3/8 × 9 C6 114 × 162 4 1/2 × 6 3/8 C7 81 × 114 3 3/16 × 4 1/2 C8 57 × 81 2 1/4 × 3 3/16 C9 40 × 57 1 5/8 × 2 1/4 C10 28 × 40 1 1/8 × 1 5/8 Magnification Factors It is often necessary to either increase or reduce an An page in size on a photocopier, digital printer, or in a software application. In order to maintain an accurate magnification you should always use the exact percentages shown in the table below: from to A0 A2 A3 A4 A5 A6 A7 A8 A9 A10 A0 100% 50% 35% 25% 18% 12.5% 8.8% 6.2% 4.4% 3.1% A1 141% 71% 50% 35% 25% 18% 12.5% 8.8% 6.2% 4.4% A2 200% 100% 71% 50% 35% 25% 18% 12.5% 8.8% 6.2% A3 283% 141% 100% 71% 50% 35% 25% 18% 12.5% 8.8% A4 400% 200% 141% 100% 71% 50% 35% 25% 18% 12.5% A5 566% 283% 200% 141% 100% 71% 50% 35% 25% 18% A6 800% 400% 283% 200% 141% 100% 71% 50% 35% 25% A7 1131% 566% 400% 283% 200% 141% 100% 71% 50% 35% A8 1600% 800% 566% 400% 283% 200% 141% 100% 71% 50% A9 2263% 1131% 800% 566% 400% 283% 200% 141% 100% 71% A10 3200% 1600% 1131% 800% 566% 400% 283% 200% 141% 100% Envelope Formats The DL format is the most widely used business letter format envelope size. DL probably originally stood for “DIN lang” historically, but ISO 269 now explains this abbreviation more diplomatically as “Dimension Lengthwise” instead. Its size falls somewhat out of the system and equipment manufacturers have complained that it is slightly too small for reliable automatic enveloping. Therefore, DIN 678 introduced the C6/C5 format as an alternative for the DL envelope. For postal purposes, ISO 269 and DIN 678 define the following envelope formats: Format mm Content Format C6 114 × 162 A4 folded twice = A6 DL 110 × 220 A4 folded twice = 1/3 A4 C6/C5 114 × 229 A4 folded twice = 1/3 A4 C5 162 × 229 A4 folded once = A5 C4 229 × 324 A4 C3 324 × 458 A3 B6 125 × 176 C6 envelope B5 176 × 250 C5 envelope B4 250 × 353 C4 envelope E4 280 × 400 B4 North American Formats The United States, Canada, and in part Mexico, are today the only industrialized nations in which the ISO standard paper sizes are not yet widely used. Their formats are as follows: Format mm inches Letter 216 x 280 8.5 x 11.0 Legal 216 x 356 8.5 x 14.0 Executive 184 x 267 7.25 x10.5 Tabloid 279 x 431 11 x 17 Ledger 431 x 279 10.5 x 7.25 Poster Formats Quad - 1016mm x 762mm - 40in x 30in (landscape), the standard UK format. Double Quad - 1016mm x 1524mm - 40in x 60in, (portrait). A newer style, often rolled. Also called a "Subway" size or a "4 Sheet". One Sheet - 685mm x 1041mm - 27in x 41in (portrait). The British one sheet has since been mostly replaced with the Quad. Large Posters and billboards are defined as follows: 4 Sheet 1016mm x 1524mm - 40in x 60in, (portrait). This size is usually referred to as a 4 sheet poster and is regulary used for outdoor advertising. Multiples of this size are use to create large hoarding sizes; 48 sheet and 96 sheet posters. 6 Sheet More O Ferrall / Adshel / TDI / Primesites 1800mm x 1200mm (60in x 40in) Decaux 1750mm x 1185mm 48 Sheet 3048mm x 6096mm - 120in x 240in A 48 sheet poster comprising 12 x 4 sheet (60in x 40in) sections joined. European equivalent: 3m x 6m. 96 Sheet 3048mm x 12192mm - 120in x 480in A 96 sheet poster comprising of 24 x 4 sheet (60in x 40in) sections joined. European equivalent: 3m x 12m.