Answer & explanation
Counting only the part of each string that vibrates.
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
520
feet
How to estimate it
Fermi’s official “Napkin math”
Start with the 88 keys, most of which hit 3 strings. How long is a typical string? The longest is maybe 6 feet and the high notes are only inches, so call it 2 feet.
- 88 keys × 3 strings
- ≈ 260 strings
- Typical string
- ≈ 2 feet
- 260 × 2
- ≈ 520 feet
Start with the 88 keys, most of which hit 3 strings. How long is a typical string? The longest is about 2 meters and the high notes are only centimeters, so call it 70 centimeters.
- 88 keys × 3 strings
- ≈ 260 strings
- Typical string
- ≈ 70 cm
- 260 × 0.7 m
- ≈ 180 m
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Steinway D strings (8 single, 12 double, 68 triple)
- 236
- Longest, agraffe to bridge (Steinway)
- 79.25 in (201 cm)
- Vibrating lengths summed, INRIA table
- 158 m
- ≈
- 520 feet
Reference cited by Fermi: Our sum of INRIA's Steinway D string lengths (Chabassier and Durufle, 2012)
How close was your guess?
Your comparison will appear here.
Compare by ratio: divide the larger number by the smaller one. The closer to 1×, the better.