20/200Line 1 · 88.7 arcmin
S E E
Editor's markThe top line is not information. It is a promise that information is coming. Nobody misreads it; nobody remembers it either.
20/100Line 2 · 44.3 arcmin
F P T O Z
OptotypeSloan letters, ten glyphs, equal difficulty. Beauty in a chart is the absence of a favourite letter.
20/70Line 3 · 31.0 arcmin
A HEADLINE
NoteSet large enough, any sentence sounds true. Scale is the cheapest rhetorical device a designer owns.
20/50Line 4 · 22.2 arcmin
IS A CLAIM YOU
NoteHere the reader still leans back. Comfort is the enemy of scrutiny.
20/40Line 5 · 17.7 arcmin
HAVE NOT YET TESTED
Legal minimumThe line most driving licences require. Half the room stops improving here and never notices.
20/30Line 6 · 13.3 arcmin
THE ARGUMENT NARROWS FROM HERE
NoteType size and confidence fall together. Watch your chin come forward.
20/25Line 7 · 11.1 arcmin
DETAIL IS WHERE PUBLISHERS HIDE THE COST
NoteNothing has been concealed. It has only been set smaller, which is the same thing at twenty feet.
20/20Line 8 · 8.9 arcmin
Normal vision is not perfect vision — it is the median of a large, tired population measured in a small, bright room. The chart flatters us by calling the middle of the distribution “normal,” and we have been quoting that compliment back at each other since 1862.
BaselineReference acuity. The line everyone claims and roughly a third of readers genuinely hold.
20/15Line 9 · 6.7 arcmin
Below the baseline the reading changes character. You are no longer receiving a message; you are decoding one, letter by letter, guessing at the O that might be a C. This is the exact condition of most contracts, most privacy notices, and most of the terms under which our attention is bought — legible in the strict sense, unread in every sense that matters. A publisher who sets the caveat at this size has technically told you. The chart is honest about what that word technically is worth.
ThresholdSharper than reference. Comfortable only for young eyes and good light.
20/10Line 10 · 4.4 arcmin
The last line exists to be failed. Charts print it because a test with no floor cannot measure a ceiling, and publications print their equivalent because a page with no fine print looks suspiciously simple. If you can read this without leaning in, you have roughly the acuity of a well-rested hawk and our sincere congratulations; if you cannot, you have learned the only thing this issue set out to teach, which is that legibility is a relationship between a reader, a distance and a decision made by someone else about how small to set the truth. We set it small on purpose. Drag the diopter dial and watch the argument dissolve upward, line by line, until only the promise at the top survives — S, E, E.
FloorBeyond reference. Recorded, rarely resolved, always printed.