Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
80
liters
How to estimate it
Fermi’s official “Napkin math”
Your own heart pushes out about 70 milliliters a beat, roughly a shot glass. How much bigger is a blue whale than you? About a thousand times over, 70 tonnes against 70 kilograms. Scale the beat the same way.
- A human heartbeat
- ≈ 70 ml
- Whale is ~1,000x a person's mass
- × 1,000
- 70 ml × 1,000
- ≈ 70 liters
Your own heart pushes out about 2 ounces a beat, a shot glass worth. How much bigger is a blue whale than you? About a thousand times over, 150,000 pounds against 150. Scale the beat the same way.
- A human heartbeat
- ≈ 2 oz
- Whale is ~1,000x a person's weight
- × 1,000
- 2,000 oz
- ≈ 16 gallons
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Reference blue whale mass (tagged individual, 2019 study)
- ≈ 70,000 kg
- Modeled stroke volume from that mass (Goldbogen et al., PNAS 2019)
- ≈ 80 L per beat
Reference cited by Fermi: Goldbogen et al., Proceedings of the National Academy of Sciences (2019), via Stanford News
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