{
  "title": "A-series paper sizes A0 to A10, ideal and listed",
  "description": "Paper sizes A0 to A10: the ideal sides computed from the definition (ratio √2, A0 area 1 m²), the listed sides as given by Markus Kuhn for ISO 216, how each listed size was rounded, the listed long-to-short ratio and the ideal area.",
  "license": "CC BY 4.0",
  "license_url": "https://creativecommons.org/licenses/by/4.0/",
  "creator": "Drawn Mathematics",
  "page": "https://drawnmathematics.com/crease-patterns/a4-paper-size/",
  "derived_from": [
    "Listed sizes A0 to A10: Markus Kuhn, International standard paper sizes, https://www.cl.cam.ac.uk/~mgk25/iso-paper.html (last modified 2025-12-08, read 2026-10-26), CC BY 4.0",
    "Ideal sizes: short side 2^(−1/4 − n/2) m and long side 2^(1/4 − n/2) m for size An, computed for this page and shown to 0.01 mm",
    "Rounding check: starting from the listed A0 (841 × 1189 mm, the ideal A0 rounded to whole mm), each long side halved and rounded down as Kuhn describes; this reproduces every listed size"
  ],
  "method": "Compiled by Drawn Mathematics from the data listed",
  "data_credit": [
    "Listed sizes: Markus Kuhn, \"International standard paper sizes\", https://www.cl.cam.ac.uk/~mgk25/iso-paper.html, CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/)",
    "Ideal sizes, ratios and areas computed for this page from the definition of the A series (ratio √2, A0 area 1 m²)"
  ]
}