All Fermi answers
Fermi #1 · Question 1

How many piano tuners work in New York City?

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

1QUESTION 1 OF 3

Answer & explanation

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

Answer & explanation

Official answer

130

tuners

How to estimate it

Fermi’s official “Napkin math”

The easiest place to start is NYC's 3 million households. How many own a piano? Not many, maybe 1 in 50. Each gets tuned about once a year, and one tuner handles roughly 500 a year.

NYC households
~3,000,000
Own a piano
~1 in 50
One tuner does ~500/yr
÷ 500
60,000 ÷ 500
≈ 120

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

Source calculation & reference
Households in NYC
≈ 3.3 M
Share with a piano
× 1.5 %
Tunings per piano per year
× 1
Tunings one tuner does / year
÷ 380
≈ 3,300,000 × 0.015 ÷ 380
≈ 130

Reference cited by Fermi: Fermi's classic estimation problem

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