A4 A4 is a paper size that is used for a wide range of documents, including magazines, catalogs, letters and forms. Dimensions A4 measures 210- 297 millimeters or 8.27-11.69 inches. In PostScript, its dimensions are rounded off to 595 -842 points. Folded twice, an A4 sheet fits in a C6 size envelope (114 - 162 mm). Part of the ISO 216 standard A4 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. A4 is actually often referred to as DIN A4. The Japanese have adopted the same range of paper sizes in their JIS P 0138-61 standard.
