Fermi
Five impossible quantities. Being within ten times is respectable.
Type your best estimate. Order of magnitude is what matters.
About Fermi
Estimate five quantities nobody knows offhand — how many words in a long novel, how many breaths in a day. Scored on a logarithmic scale, so being within a factor of two is excellent and a factor of ten still counts.
- How to play: Type your best estimate. Order of magnitude is what matters.
- A go takes about 45 seconds. The daily puzzle is identical for every player and resets at your local midnight.
- Share any score as a challenge link — whoever opens it faces the same puzzle with your number to beat.
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