All Fermi answers
Fermi #36 · Question 2

How many times does the average person blink in a day?

Explore the official answer and the simple reasoning behind this Fermi estimate.

2QUESTION 2 OF 3

Answer & explanation

The official answer, with Fermi’s reasoning step by step.

Answer & explanation

Official answer

15,000

blinks

How to estimate it

Fermi’s official “Napkin math”

You blink without ever thinking about it. How often? Maybe 15 times a minute. You're awake around 16 hours, which is about 1,000 minutes.

Blinks per minute
~15
Waking minutes
× ~1,000
15 × 1,000
≈ 15,000

Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.

Source calculation & reference
Blinks per minute
~15-20
Waking minutes (16 hrs)
~1,000
Roughly
≈ 15,000

Reference cited by Fermi: American Academy of Ophthalmology / Harvard: ~15-20 blinks per minute

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