All Fermi answers
Fermi #14 · Question 1

How many active certified scuba divers are there worldwide?

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

6,000,000

divers

How to estimate it

Fermi’s official “Napkin math”

The easiest handle is the US, far and away the biggest dive market. Something like 3 million Americans get in the water in a given year. Diving is a rich country hobby and the US is about half of it, so double.

Active divers in the US
~3,000,000
US share of the world
~1/2
3M × 2
≈ 6,000,000

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

Source calculation & reference
PADI certifications issued since 1967
> 30 million
But a card is for life, and most stop diving
~1 in 5 still active
DEMA active divers worldwide
≈ 6 million

Reference cited by Fermi: DEMA Diving Fast Facts

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