Automotive calculators

Horsepower & Torque Calculator

Calculate one missing value from horsepower, torque, and rotational speed. This is a mathematical conversion, not a dyno measurement.

Calculated result

Formula and method

Mechanical hp = torque (lb·ft) × RPM ÷ [33,000 ÷ (2π)], where the exact conversion denominator is approximately 5,252.113. Rearrange to solve torque or RPM. 1 lb·ft = 1.3558179483314004 N·m.

Worked example

300 lb·ft at 5,252 RPM is approximately 299.994 mechanical hp.

How to use this calculator

Enter the requested measurements, choose the units, and select Calculate. Change values and calculate again to compare scenarios. Results keep full numeric precision internally and round only for display.

Limits and common questions

Calculated crankshaft-equivalent values are not measured engine or wheel output. The relation applies at the same operating RPM; it is not a torque-curve estimate.

Are these values measured or estimated?

They are calculations from the inputs you provide, not independent measurements of a particular vehicle.

Are my inputs saved?

No. This calculator works in your browser tab without an account, upload, or calculator-input storage.