A2

A2 is a paper size that is often used for medium size posters, architectural drawings and diagrams.

Dimensions

A2 measures 420 × 594 millimeters or 16.54 × 23.39 inches. In PostScript, its dimensions are rounded off to 1190 × 1684 points.

Part of the ISO 216 standard

A2 is part of a set or range of page sizes, called the ISO A or ISO 216 standard. This international standard is based on the German DIN 476 standard from 1922. A5 is actually often referred to as DIN A5. The Japanese have adopted the same range of paper sizes in their JIS P 0138-61 standard.

By folding an A2 in two along its shortest side, you create an A3 document. Two A2 pages next to each other in a spread equals the A1 paper size. This way a range of paper sizes are created from A0 (which has a surface of one square meter) to A10. The height/width ratio remains constant (1:1.41 or the square root of 2) for all sizes. The dimensions always get rounded to the nearest millimeter.

Alternatives

In the American market ISO paper sizes are hardly used at all. The US-alternative to A2 is called ANSI C and measures 17 × 22″ or 432 × 559 mm.

Other sources of information

An elaborate yet easy to read page on the ISO 216 standard can be found here.