A4 Paper Is Too Perfect

CGP Grey · explainer · Watch on YouTube

What it is

CGP Grey explains the elegant ratio of A4 and the metric paper sizes, then zooms out across scales from the Planck length to the observable universe.

Loved for its zoom-out tour of physical scales and recommended alongside other paper-size and scale-of-the-universe discussions.

“the most psychedelic experience one can have without doing drugs”
Favorite CGP Grey video; psychedelic tour from Planck lengths to observable universe.
ProllyInfamous, 2026-01 · Strong recommendation · in “A4 Paper Stories”
“that is well worth a watch if you haven't seen it.”
Deeper detail into metric paper, well worth a watch.
jihadjihad, 2026-01 · Recommendation · in “A4 Paper Stories”

Excerpts from Hacker News comments, linked to the originals. Summaries and labels were written by a language model from those comments.

Topics: a4 paper, metric system, scale of the universe, iso 216, cgp grey