Fermi question · Everyday
According to EPA WaterSense information available in 2026, about how many gallons of water does the average American use at home per day?
Make a fast, defensible estimate before you reveal the reference answer. Think in factors, not exact recall.
What is your estimate?
Your result will appear here after you submit a guess.
Reference answer
Reveal the reference answer
≈ 82 gallons per person per day
Fermi estimates are judged by scale, so a reasonable approximation can still earn a strong score.
One way to estimate it
Estimate household water use by combining several common daily uses.
- Bathing and toilets≈ 45 gallons/person/day
- Laundry, faucets, dishes and other uses≈ 35–40 more gallons/person/day
- Estimate≈ 80 gallons/person/day
Keep practicing
Try another question, or return to the daily challenge to build your personal sense of scale.