Convert Joules to Foot-pounds
1 joule (J) equals 0.7375621493 foot-pounds (ft·lbf).
1 J = 0.7375621493 ft·lbf
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk joule to foot-pound converter to paste a column from Excel.
How to Convert Joule to Foot-pound
- 1 J = 0.7375621493 ft·lbf
- 1 ft·lbf = 1.355817948 J
- Example: convert 15 J to ft·lbf: 15 J = 15 × 0.7375621493 ft·lbf = 11.06343224 ft·lbf
Formula
ft·lbf = J × 0.7375621492773
or ft·lbf = J ÷ 1.355817948331
Derivation from SI units:
- 1 J = 1 N·m = 1 W·s = 1 kg·m²·s⁻²
- 1 ft·lbf = 0.3048 m × 4.4482216152605 N = 1.3558179483314 J
Both units are defined exactly, so the factor is exact. Joule definition: joule; Foot-pound definition: foot-pound.
Worked examples
- The UK air-rifle limit of about 16.3 J is 12.02226303 ft·lbf.
16.3 J × 0.7375621493 = 12.02226303 ft·lbf - A Charpy test energy of 300 J is 221.2686448 ft·lbf.
300 J × 0.7375621493 = 221.2686448 ft·lbf
Joule to Foot-pound conversion table
| Joules (J) | Foot-pounds (ft·lbf) |
|---|---|
| 1 J | 0.7375621493 ft·lbf |
| 10 J | 7.375621493 ft·lbf |
| 100 J | 73.75621493 ft·lbf |
| 250 J | 184.3905373 ft·lbf |
| 500 J | 368.7810746 ft·lbf |
| 1000 J | 737.5621493 ft·lbf |
| 4184 J | 3085.960033 ft·lbf |
| 10000 J | 7375.621493 ft·lbf |
| 100000 J | 73756.21493 ft·lbf |
| 1000000 J | 737562.1493 ft·lbf |
| 3600000 J | 2655223.737 ft·lbf |
Where it's used
SI energies are converted to foot-pounds for US ammunition data, impact testing and mechanical work.
Joule to other energy units
| Conversion | 1 J equals |
|---|---|
| joule to kilojoule | 0.001 kJ |
| joule to megajoule | 0.000001 MJ |
| joule to calorie | 0.2390057361 cal |
| joule to kilocalorie | 0.0002390057361 kcal |
| joule to watt-hour | 0.0002777777778 Wh |
| joule to kilowatt-hour | 2.777777778 × 10⁻⁷ kWh |
| joule to BTU | 0.0009478171203 BTU |
| joule to therm | 9.48043428 × 10⁻⁹ thm |
| joule to electronvolt | 6.241509074 × 10¹⁸ eV |
| joule to foot-pound | 0.7375621493 ft·lbf |
| joule to erg | 10000000 erg |
Frequently asked questions
How many ft·lb is 1 joule?
1 J = 0.7375621493 ft·lbf.
How many foot-pounds are in 1 joule?
1 J = 0.7375621493 ft·lbf.
How do I convert joules to foot-pounds?
Multiply the value in J by 0.7375621493, or divide it by 1.355817948. For example, 15 J × 0.7375621493 = 11.06343224 ft·lbf.
Is the J to ft·lbf conversion exact?
Yes. Both units are defined exactly, so the ratio is exact; its decimal form does not terminate and is shown here to 10 significant figures (more with the precision selector).
Sources
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 4, coherent derived units with special names.
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "foot pound-force (ft·lbf)".
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Joules to Foot-pounds. Retrieved October 17, 2026, from https://scientificconverters.com/energy/joules-to-foot-pounds/
IEEE
Scientific Converters, "Convert Joules to Foot-pounds," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/energy/joules-to-foot-pounds/