Solve for horsepower, torque, or RPM when you know the other two values using the classic engine equation. Horsepower equals torque in pound feet times engine speed in RPM divided by 5252, a constant that comes from the definition of one horsepower. This is why dyno curves for horsepower and torque always cross at 5252 RPM. Leave any one field blank or enter zero and this calculator fills it in from the other two, so you can find peak horsepower from a torque figure, back out torque from a power rating, or work out the RPM where a given power is produced. It is useful for tuners reading dyno sheets, students, and anyone comparing engines quoted in different terms. The math is exact for pound feet and RPM, and everything runs in your browser.
It uses horsepower equals torque times RPM divided by 5252, the classic relation for foot pounds and mechanical horsepower.
The 5252 constant comes from converting units so that horsepower and torque curves cross at 5252 RPM.
Yes. Provide any two of horsepower, torque, and RPM and it solves for the remaining one.
Solve for horsepower, torque, or RPM when you know the other two values using the classic engine equation. Horsepower equals torque in pound feet times engine speed in RPM divided by 5252, a constant that comes from the definition of one horsepower.
Yes. Horsepower Torque RPM Calculator is completely free, with no sign-up and no usage limits.
Yes. Horsepower Torque RPM Calculator runs in any modern web browser. There is nothing to download or install.
Yes. Horsepower Torque RPM Calculator runs entirely on your device in your browser, so nothing you enter is uploaded to a server.