How to use the torque converter
- Type your torque in the From box. Decimals (12.5) and thousands separators (1,250) both work.
- Pick the unit you have in the first menu and the unit you want in the second. The To box and the result line update as you type.
- To work backwards, type in the To box and the From box follows.
- Press Swap units to flip the direction, or read Same torque in every unit to see your number in all ten other units at once.
How the conversion works
Every unit is stored as a size in newton-meters. The tool multiplies your number by the size of the From unit, then divides by the size of the To unit: result = value × From size ÷ To size. A pound-force is defined as exactly 4.4482216152605 N (0.45359237 kg × 9.80665 m/s²), so 1 ft-lb = 4.4482216152605 N × 0.3048 m = 1.3558179 N·m, 1 in-lb = 0.11298483 N·m, and 1 ft-lb = 12 in-lb. A kilogram-force is exactly 9.80665 N. The factors match NIST Guide to the SI, Appendix B.8. Foot-pound here means pound-force foot, also written lb-ft: the number is the same either way.
Worked example with the default values
With 100 in the From box, N·m as the From unit and ft-lb as the To unit, the result line reads 100 N·m = 73.756215 ft-lb, because 100 ÷ 1.3558179 = 73.756215. The reverse line reads 1 ft-lb = 1.3558179 N·m, and the grid shows the same torque as 885.07458 in-lb and 10.197162 kgf·m.
Common torque conversions
| ft-lb | Equals | N·m | Equals |
|---|---|---|---|
| 10 ft-lb | 13.558179 N·m | 10 N·m | 7.3756215 ft-lb |
| 20 ft-lb | 27.116359 N·m | 20 N·m | 14.751243 ft-lb |
| 25 ft-lb | 33.895449 N·m | 25 N·m | 18.439054 ft-lb |
| 50 ft-lb | 67.790897 N·m | 50 N·m | 36.878107 ft-lb |
| 80 ft-lb | 108.46544 N·m | 80 N·m | 59.004972 ft-lb |
| 100 ft-lb | 135.58179 N·m | 100 N·m | 73.756215 ft-lb |
| 120 ft-lb | 162.69815 N·m | 120 N·m | 88.507458 ft-lb |
| 150 ft-lb | 203.37269 N·m | 150 N·m | 110.63432 ft-lb |
| 200 ft-lb | 271.16359 N·m | 200 N·m | 147.51243 ft-lb |
Matching torque to power? The horsepower and torque calculator links torque, rpm and horsepower. For kW and hp use the power converter, for joules and foot-pounds of energy the energy converter, and for other quantities the unit converter.
Limits and edge cases
Negative values convert normally. Letters and slashes are blocked with a hint, and anything above 1e24 is refused. This page only changes units: the right torque for a lug nut, spark plug or cylinder head comes from your vehicle service manual and varies by thread, lubrication and model. Hobby servos are often rated in kgf·cm and stepper motors in oz-in, both of which are in the menus.
Sources: NIST Guide to the SI, Appendix B.8; ISO 6789 for torque wrench tolerance.
Torque converter FAQ
How do I convert Nm to ft-lb?
Multiply the newton-meters by 0.73756215. For example, 100 N·m × 0.73756215 = 73.756215 ft-lb. Equivalently, divide by 1.3558179.
How do I convert ft-lb to Nm?
Multiply the foot-pounds by 1.3558179. For example, 100 ft-lb × 1.3558179 = 135.58179 N·m, and 80 ft-lb is 108.46544 N·m.
How many inch-pounds are in a foot-pound?
Exactly 12, because a foot is 12 inches. So 1 ft-lb = 12 in-lb, and 1 in-lb = 0.11298483 N·m.
Is a newton-meter the same as a joule?
The two share the same base units, but they are different quantities. Torque is a force times a lever arm at right angles to it, while a joule measures energy. Write torque as N·m and keep J for energy.
How accurate is a click-type torque wrench?
Most click-type wrenches are rated to about plus or minus 4 percent of the set value, and only between roughly 20 and 100 percent of their range (ISO 6789). At 100 N·m that means a real torque anywhere from 96 to 104 N·m.