Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
22.6
meters
How to estimate it
Fermi’s official “Napkin math”
Come at it through people. There are 8 billion of us, and gold is mostly jewellery. How much would everyone get if you split it evenly? About a ring's worth, call it 25 grams. Gold is heavy, roughly 20 times water.
- People on Earth
- 8,000,000,000
- Gold each
- × 25 g
- 8B × 25 g
- ≈ 200,000 tonnes
- ÷ 20 tonnes per m³, then cube root
- ≈ 22 meters
Come at it through people. There are 8 billion of us, and gold is mostly jewellery. How much would everyone get if you split it evenly? About a ring's worth, call it an ounce. Gold is heavy, maybe 1,000 pounds a cubic foot.
- People on Earth
- 8,000,000,000
- Gold each
- × 1 oz
- 8B oz
- ≈ 500,000,000 lb
- ÷ 1,000 lb per cu ft, then cube root
- ≈ 79 feet
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Gold ever mined, end Q2 2026 (World Gold Council)
- 222,600 tonnes
- Density of gold
- 19.3 tonnes per m³
- 222,600 ÷ 19.3
- ≈ 11,530 m³
- Cube root of 11,530
- ≈ 22.6 meters
Reference cited by Fermi: World Gold Council above-ground stocks (222,600 tonnes at end-Q2 2026), whose own page puts the resulting cube at about 22.6 metres a side
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