Markus Kuhn’s International Standard Paper Sizes¹ is a great document on ISO-216 paper sizes, if you want a little more depth than HelloNurse’s succinct description. It also covers US-style sizes toward the bottom.
Kuhn also has an excellent ISO-8601 document², which makes you wish he would dive through more of the common standards that ISO stand guard over.
Now I'm confused. The article says at one point that ANSI "letter" is 8 1/2 inches by 12 2/3 inches and also that "letter" size is 8 1/2 inches by 11 inches without explaining the discrepancy. So which is it?
Comments
Regarding A, B and C ISO sizes, they aren't mysterious:
- the aspect ratio is square root of 2 to 1, so that cutting in half the long side leaves two sheets with the same aspect ratio.
- A is the main series, with A0 approximately one square meter.
- B sizes are square root of 2 times larger in area than A formats with the same numbers, filling the gaps.
- C sizes are slightly larger than A sizes, suitable for containers, envelopes etc. for them.
Markus Kuhn’s International Standard Paper Sizes¹ is a great document on ISO-216 paper sizes, if you want a little more depth than HelloNurse’s succinct description. It also covers US-style sizes toward the bottom.
Kuhn also has an excellent ISO-8601 document², which makes you wish he would dive through more of the common standards that ISO stand guard over.
¹ https://www.cl.cam.ac.uk/~mgk25/iso-paper.html
² https://www.cl.cam.ac.uk/~mgk25/iso-time.html - Sadly only covers timestamps, not durations/intervals/etc
Now I'm confused. The article says at one point that ANSI "letter" is 8 1/2 inches by 12 2/3 inches and also that "letter" size is 8 1/2 inches by 11 inches without explaining the discrepancy. So which is it?