Calculate horsepower, torque, or RPM from two measurements at the same shaft and operating point, with mechanical HP, metric PS, kW, watts, lb-ft, N·m, and lb-in conversions.
HP to Torque Formula
The following approximate formula calculates torque from mechanical horsepower. The calculator uses P = T × 2π × RPM / 60 in SI units; the familiar 5252 factor is rounded from about 5252.113122.
- Where T is the torque (pound-feet)
- HP is the horsepower
- RPM is the rotations per minute
To calculate torque from HP, divide the horsepower by the value of the RPM divided by 5252.
| Horsepower (HP) | Torque (lb-ft) | Torque (N·m) |
|---|---|---|
| 5 | 8.753 | 11.868 |
| 10 | 17.507 | 23.736 |
| 15 | 26.260 | 35.604 |
| 20 | 35.013 | 47.472 |
| 25 | 43.767 | 59.340 |
| 30 | 52.520 | 71.208 |
| 40 | 70.027 | 94.944 |
| 50 | 87.533 | 118.679 |
| 60 | 105.040 | 142.415 |
| 75 | 131.300 | 178.019 |
| 100 | 175.067 | 237.359 |
| 125 | 218.833 | 296.699 |
| 150 | 262.600 | 356.038 |
| 200 | 350.133 | 474.718 |
| 250 | 437.667 | 593.397 |
| 300 | 525.200 | 712.077 |
| 400 | 700.267 | 949.436 |
| 500 | 875.333 | 1186.794 |
| 600 | 1050.400 | 1424.153 |
| 1000 | 1750.667 | 2373.589 |
| * Rounded to 3 decimals. Uses HP–Torque relation at fixed RPM: Torque (lb-ft) = 5252 × HP ÷ RPM; Torque (N·m) = lb-ft × 1.35582. Table assumes RPM = 3000. | ||
HP to Torque Definition
Torque equals power divided by angular speed. Use power and RPM measured at the same shaft and operating point; do not combine peak horsepower and peak torque at different engine speeds.
HP to Torque Example
How to convert hp to torque?
- First, determine the horsepower.
Measure the total engine horsepower.
- Next, determine the RPM.
Measure the RPM generated by the engine.
- Finally, calculate the torque.
Calculate the torque using the equation above.
FAQ
RPM stands for rotations per minute and is typically used in the field of automobiles.
