Convert Foot-pounds to Kilojoules
1 foot-pound is 0.001356 kJ. One foot-pound is exactly 0.00135581794833 kilojoules.
One foot-pound is 0.0013558179 kilojoules. To convert foot-pounds to kilojoules, multiply by 0.0013558179; to go the other way, divide by 0.0013558179 or multiply by 737.56215. 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 × 0.0013558179
value * 0.001355817948330.001 kJ
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 kilojoules?
- 1.Take the measurement in foot-pounds.
- 2.Multiply by 0.0013558179 — that is how many kilojoules fit in one foot-pound.
- 3.To go back the other way, divide by 0.0013558179, or multiply by 737.56215.
Worked example: 25 foot-pounds to kilojoules
- Formula
- ft·lbf × 0.0013558179 = kJ
- Arithmetic
- 25 × 0.0013558179 = 0.033895 kJ
- Answer
- 25 ft·lbf = 0.033895 kJ
The factor is rounded for display; the figure above is computed from the full value.
Foot-pounds to kilojoules conversion table
| Foot-pounds | Kilojoules |
|---|---|
| 1 ft·lbf | 0.001356 kJ |
| 2 ft·lbf | 0.002712 kJ |
| 3 ft·lbf | 0.004067 kJ |
| 4 ft·lbf | 0.005423 kJ |
| 5 ft·lbf | 0.006779 kJ |
| 6 ft·lbf | 0.008135 kJ |
| 7 ft·lbf | 0.009491 kJ |
| 8 ft·lbf | 0.010847 kJ |
| 9 ft·lbf | 0.012202 kJ |
| 10 ft·lbf | 0.013558 kJ |
| 12 ft·lbf | 0.01627 kJ |
| 15 ft·lbf | 0.020337 kJ |
| 20 ft·lbf | 0.027116 kJ |
| 25 ft·lbf | 0.033895 kJ |
| 50 ft·lbf | 0.067791 kJ |
| 100 ft·lbf | 0.135582 kJ |
| 200 ft·lbf | 0.271164 kJ |
| 300 ft·lbf | 0.406745 kJ |
| 500 ft·lbf | 0.677909 kJ |
| 1000 ft·lbf | 1.355818 kJ |
| 2000 ft·lbf | 2.711636 kJ |
| 5000 ft·lbf | 6.77909 kJ |
| 10000 ft·lbf | 13.558179 kJ |
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 kilojoule?
A thousand joules. Food energy outside the US is labelled here, alongside or instead of calories.
How many kilojoules are in a foot-pound?
One foot-pound is 0.0013558179 kilojoules. Going the other way, one kilojoule is 737.56215 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 kilojoules are in a foot-pound?
- 0.0013558179. A thousand joules. Food energy outside the US is labelled here, alongside or instead of calories.
- How do I convert kilojoules back to foot-pounds?
- Divide by 0.0013558179, or multiply by 737.56215 — they are the same operation.
Other energy conversions
Kilojoules to foot-pounds — the same conversion the other way.