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A4 Paper Is Too Perfect

Name: A4 Paper Is Too Perfect
Description: 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.

CGP Grey Explainers

Open on YouTube First HN thread

2 HN users recommended this explainer in 2 different months between 2024 and 2026.

2007–2026

2 strong recommendations 1 recommendation 2 citations HackerTube score 3

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

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.

Pull quote: “the most psychedelic experience one can have without doing drugs” (HN, 2026)

Also tagged: a4 paper sizes, a4 paper, metric system, scale of the universe, iso 216, cgp grey

What Hacker News said

5 labeled comments from the HN archive; up to 20 are kept per video, favoring different commenters. Each one links back to the original thread.

Strongly recommends ProllyInfamous January 2026 under A4 Paper Stories

Favorite CGP Grey video; psychedelic tour from Planck lengths to observable universe.

You beat me in posting this (I searched for "CGP," first — you mispelled so I didn't see your comment). ---- My favorite CGP Grey video is Metric Paper... , which explores the vast (but limited) world we live in, from plancs to observable universe. [•] < [this video] > Before generative AI videos, this had been what I considered "the most psychedelic experience one can have without doing drugs ." It's still a trip ...

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Strongly recommends ProllyInfamous April 2026 under God Sleeps in the Minerals

Zoom-out video among commenter's favorites.

Zoom out, too: [CGP Grey - Metric Paper] < [this video] > - among my favorite videos Yet even Plancks remain analogue ...

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Recommends jihadjihad January 2026 under A4 Paper Stories

Deeper detail into metric paper, well worth a watch.

CPG Grey has a video [0] that goes into some, let's just say deeper , detail into metric paper that is well worth a watch if you haven't seen it. 0: [this video]

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Citations, criticism and jokes

Cites it xanth February 2024 under Making a PDF that's larger than Germany

Compares metric paper sizes to objects from Planck scale to galactic.

Related CGPGrey video comparing metric paper sizes to comparable objects from the plank scale to the galactic[1]; could have been an XKCD comic [1]: [this video]

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Cites it bogtog April 2024 under Scale of the Universe

Another zoom in/out telling of physics scales.

I think this Zoom in/out physics story has pretty widely been told. Here is one by CPG Grey: [this video] I like the one OP linked here. All the objects being clickable with a little description is nice

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