Popular office paper standards
Paper formats refer to the standard size of the paper sheet. Different countries at various times have had different standard paper sizes. Currently there are two systems which dominate in the world: the international standard discussed below (applied in most of Europe) and the North American standard (used in the English speaking world).
Paper formats ISO 216 international standard
The international standard for paper standards ISO 216 is based on the metric system and paper sheets with an area of 1 sq. m. This standard is employed by all countries, except the USA and Canada. The American standard is still widely used in Mexico and the Philippines, regarless of their acceptance of the international standard. The most popular and well-known format of the ISO 216 standard is А4. All paper formats of ISO 216 have the same width/height ratio, equal to square root of 2 (approximately, 1:1,4142). The advantage of using such a proportion of the paper sheet has been noted in 1768 г. by the German scientist Georg Lichtenberg. At the beginning of the 20th century Dr Walter Porstmann applied this idea on the paper formats.
Paper formats ISO 216 – А series
The most popular office paper formats applied worldwide are the A series of ISO 216. They are shown in the following table by designation, corresponding size in mm, and the recommended polygraphic paper size they are derived from.
| ISO code | ISO size, mm | Recommended polygraphic sheet size | |
|---|---|---|---|
| A0 | 841 x 1189 mm | ||
| A1 | 594 x 841 mm | ||
| A2 | 420 x 594 mm | 600x840 mm, 600x900 mm | |
| A3 | 297 x 420 mm | 600x900 mm | |
| A4 | 210 x 297 mm | 600x900 mm | |
| A5 | 148 x 210 mm | 600x900 mm | |
| A6 | 105 x 148 mm | 600x900 mm | |
The figure below summarises the correspondence of sizes within the A series, and the relation to the most popular American size of and the larger (both approximately corresponding to A4 in the ISO system).

