Fermi

Quiz

Three questions every day that nobody knows by heart, but that you can reason out with a little intuition. The closest guess wins.

Need help, or found a mistake in a question?

Tell us and we’ll look into it.

Frequently asked questions

When does the new challenge arrive?: Every day at midnight, Madrid time.
How is it scored?: Your score is the average miss across your three answers: how many times off you are from the reference answer. The closer to 1×, the better.
Do hints cost points?: No. They only show up in the result you share.
Can I play earlier challenges?: Yes, in the Archive tab. They count towards your stats, but your streak only grows with the challenge of the day.
Do I need an account or a connection?: No. Fermi Quiz works offline and your progress is saved on your iPhone.
How do I enter very large numbers?: Use the × thousand and × million buttons, or “More…” for powers of ten.