Sizing up paper around the world

Americans will be familiar with the common paper sizes of ‘letter’, ‘ledger’, and ‘tabloid’, but did you know that these are rarely used outside of this continent? Instead, the rest of the world uses the ISO 216 standard.

Most paper within this standard comes from the A Series, which includes 11 different sizes. The biggest of these is A0, which measures 1,189mm long and 841mm wide. A1 is half this size, and A2 is in turn half the size of A1. In each case, the width of the paper becomes the length of the one smaller than it. This series extends right down to A10, which is about the size of a postage stamp at 26mm x 37mm. The most regularly used size is A4, which is similar to ‘letter’ paper over here.

An interesting factoid for those with a mathematical mind is that the length of an A Series sheet of paper is always the width multiplied by the square root of two, which is roughly 1.414. For example, an A4 sheet is 210mm wide. Multiply this by 1.414, and you come very close to the required width of 297mm.

Print companies outside of North America will also be familiar with the B Series, which maintains the ratio of 1:1.414, but starts with the extremely large B0 boasting a width of 1,000mm. There is also a C series, with C0 fitting between A0 and B0 in size.

It all goes to show that, wherever you are in the world, size matters – at least on paper!