All Fermi answers
Fermi #39 · Question 3

How many bicycles are there in Amsterdam?

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

3QUESTION 3 OF 3

Answer & explanation

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

Answer & explanation

Official answer

880,000

bicycles

How to estimate it

Fermi’s official “Napkin math”

Start with Amsterdam's population, a bit under a million. How many of them own a bike? Almost everyone, and plenty own two, a good one plus a beater to leave at the station.

Amsterdam's population
≈ 900,000
Bikes per person
× 1
900,000 × 1
≈ 900,000

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

Source calculation & reference
City of Amsterdam resident survey estimate
≈ 881,000 bicycles
Cross-check: 443,000 households × 1.9 bikes each (CBS)
≈ 847,000
≈
880,000

Reference cited by Fermi: CROW-Fietsberaad · City of Amsterdam survey estimate

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