Convert Foot-pounds to Watt-hours
1 foot-pound is 0.000377 Wh. One foot-pound is exactly 0.000376616096759 watt-hours.
One foot-pound is 3.7662 × 10^-4 watt-hours. To convert foot-pounds to watt-hours, multiply by 3.7662 × 10^-4; to go the other way, divide by 3.7662 × 10^-4 or multiply by 2655.2237. The factor is exact rather than rounded: it follows from NIST Special Publication 811. A pound-force acting through one foot.
Factor checked against the defining standard · How we check
- Foot-pounds × 3.7662 × 10^-4
value * 0.0003766160967590 Wh
1 foot-pound in every energy unit
| Unit | Value | Exact factor |
|---|---|---|
| joules | 1.355817948 J | × 1.35581794833 |
| kilojoules | 0.001355817948 kJ | × 0.00135581794833 |
| calories | 0.3240482668 cal | × 0.32404826681 |
| kilocalories | 0.0003240482668 kcal | × 0.00032404826681 |
| watt-hours | 0.0003766160968 Wh | × 0.000376616096759 |
| kilowatt-hours | 0.0000003766160968 kWh | × 0.000000376616096759 |
| British thermal units | 0.001285067463 BTU | × 0.00128506746346 |
| foot-pounds (as entered) | 1 ft·lbf | — |
Factors are entered by hand from NIST Special Publication 811 rather than derived from a units library, so the ones that terminate are exact rather than rounded.
How do you convert foot-pounds to watt-hours?
- 1.Take the measurement in foot-pounds.
- 2.Multiply by 3.7662 × 10^-4 — that is how many watt-hours fit in one foot-pound.
- 3.To go back the other way, divide by 3.7662 × 10^-4, or multiply by 2655.2237.
Worked example: 25 foot-pounds to watt-hours
- Formula
- ft·lbf × 3.7662 × 10^-4 = Wh
- Arithmetic
- 25 × 3.7662 × 10^-4 = 0.009415 Wh
- Answer
- 25 ft·lbf = 0.009415 Wh
The factor is rounded for display; the figure above is computed from the full value.
Foot-pounds to watt-hours conversion table
| Foot-pounds | Watt-hours |
|---|---|
| 1 ft·lbf | 0.000377 Wh |
| 2 ft·lbf | 0.000753 Wh |
| 3 ft·lbf | 0.00113 Wh |
| 4 ft·lbf | 0.001506 Wh |
| 5 ft·lbf | 0.001883 Wh |
| 6 ft·lbf | 0.00226 Wh |
| 7 ft·lbf | 0.002636 Wh |
| 8 ft·lbf | 0.003013 Wh |
| 9 ft·lbf | 0.00339 Wh |
| 10 ft·lbf | 0.003766 Wh |
| 12 ft·lbf | 0.004519 Wh |
| 15 ft·lbf | 0.005649 Wh |
| 20 ft·lbf | 0.007532 Wh |
| 25 ft·lbf | 0.009415 Wh |
| 50 ft·lbf | 0.018831 Wh |
| 100 ft·lbf | 0.037662 Wh |
| 200 ft·lbf | 0.075323 Wh |
| 300 ft·lbf | 0.112985 Wh |
| 500 ft·lbf | 0.188308 Wh |
| 1000 ft·lbf | 0.376616 Wh |
| 2000 ft·lbf | 0.753232 Wh |
| 5000 ft·lbf | 1.88308 Wh |
| 10000 ft·lbf | 3.766161 Wh |
What is a foot-pound?
A pound-force acting through one foot. The same arithmetic as the torque unit of that name, and a different quantity: this one is work done, not twist applied.
What is a watt-hour?
One watt sustained for an hour, so exactly 3,600 joules. Battery capacity is quoted here because it is an amount of energy rather than a rate.
How many watt-hours are in a foot-pound?
One foot-pound is 3.7662 × 10^-4 watt-hours. Going the other way, one watt-hour is 2655.2237 foot-pounds. Both figures come from the same defined relation rather than from a measurement, which is why they are the same today as they were in 1959.
Every energy unit here
| Unit | Symbol | One of these is |
|---|---|---|
| Joules | J | the base unit |
| Kilojoules | kJ | 1000 joule |
| Calories | cal | 4.184 joule |
| Kilocalories | kcal | 4184 joule |
| Watt-hours | Wh | 3600 joule |
| Kilowatt-hours | kWh | 3600000 joule |
| British thermal units | BTU | 1055.0559 joule |
| Foot-pounds | ft·lbf | 1.3558179 joule |
Source: NIST Special Publication 811 — the thermochemical calorie is exactly 4.184 J
Questions people actually ask
- How many watt-hours are in a foot-pound?
- 3.7662 × 10^-4. One watt sustained for an hour, so exactly 3,600 joules. Battery capacity is quoted here because it is an amount of energy rather than a rate.
- How do I convert watt-hours back to foot-pounds?
- Divide by 3.7662 × 10^-4, or multiply by 2655.2237 — they are the same operation.
Other energy conversions
Watt-hours to foot-pounds — the same conversion the other way.