Guide to Poster & Page Sizes

The international standard for paper sizes is ISO 216. We sizes such as A0, A1, A2, A3, A4, A5 to make it easier for you to select the correct product.

We always uses millimeters (mm) in all measurements. Measurements mentioned in the description of a product are given in good faith but are not guaranteed as small variations can occur.

ISO 216 sizes
(mm × mm) 

A0 = 841 x 1189

A1 = 594 x 841

A2 = 420 x 594

A3 = 297 x 420

A4 = 210 x 297

A5 = 148 x 210

A6 = 105 x 148

A7 = 74 x 105

A8 = 52 x 74

A9 = 37 x 52

A10 = 26 x 37

This content is an excerpt from http://en.wikipedia.org/wiki/ISO_216