Paper Sizes...A4 or Foolscap?

With all these recent explanations of the ISO paper sizes, their measurements and corresponding envelopes, we’ve failed to explain to you one of the most basic pieces of information; the difference between A4 and Foolscap.


Foolscap paper is cut to the size of 8.5 by 13.5 inches or 215.9 mm by 342.9 mm as opposed to the A4 alternative which is 8.3 by 11.7 or 210 by 297. Foolscap paper was a traditional size used in Europe and the Commonwealth, before the adoption of the international standard A4 paper in 1975, which is the most common standard size outside the United States and Canada. Foolscap is a common size for ring binders and lever arch files used to hold A4 paper as it is slightly larger than A4 and therefore offers greater protection to the edge of the pages. Foolscap was named after the fool’s caps and bells watermark commonly used from the fifteenth century onwards. The earliest example of such paper that is firmly dated was made in Germany in 1479.

A4 paper is part of the ISO 216 paper series and is the most widely used size all over the world today. The ISO standard paper size system covers a wide range of formats, but not all of them are widely used in practice. A4 is clearly the most important one for daily office use and some main applications of this size could be; letters, magazines, forms, catalogues, laser printer and copying machine output.