All Fermi answers
Fermi #25 · Question 2

How tall is the tallest tree in the world?

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

381

feet

How to estimate it

Fermi’s official “Napkin math”

Put the tallest tree you've ever stood under next to a building. How many floors would it reach? Maybe 20, and a floor is about 10 feet. The record holder should beat it comfortably, so double it.

Floors that tree would reach
~20
Feet per floor
× 10
Double it for the record holder
× 2
20 × 10 × 2
≈ 400 ft

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

Source calculation & reference
Hyperion, a coast redwood in Redwood National Park, California
116.22 m (2026 measurement)
Convert meters to feet
× 3.28
116.22 × 3.28
≈ 381 ft

Reference cited by Fermi: Guinness World Records, tallest living tree: Hyperion, a coast redwood measured at 116.22 m (381.3 ft)

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