Vin­tage Match­Books size C8 — ISO paper size.

Do you ISO or do I?

Found out something truly fascinating today when I perused a knowledge lidbit (which is slightly more than a tidbit) concerning what the dimensions of a piece A4 paper is. Come to find out, standard paper sizes are based on a single aspect ratio of the square root of 2 or  [√2 = 1:1.4142] The way to figure out dimensions is to fold an A4 size piece of paper in half, do it again, again, again... ad infinitum. Wikipedia puts the explanation of paper sizing standards thusly: "The main advantage of this system is its scaling: if a sheet with an aspect ratio of √2 is divided into two equal halves parallel to its shortest sides, then the halves will again have an aspect ratio of √2." ... read more