About the Shaft Power and Torque Calculator Online Free Tool

The Shaft Power and Torque Calculator Online Free Tool converts between power and torque at a known rotational speed for rotating machinery and drive sizing.

How to Use the Shaft Power and Torque Calculator Online

1. Select whether you want torque from power and rpm, or power from torque and rpm.
2. Enter the known power or torque value plus shaft speed.
3. Run the calculator to get the converted value in metric and imperial units.

Choosing Options Correctly

Use shaft output power if you are sizing driven equipment, and motor input power only when losses are already included. Gearbox efficiency, service factor, shock loading, and duty cycle are not modeled.

Common Use Cases

• Size a shaft or coupling from motor power and rpm.
• Estimate motor power from a torque requirement.
• Cross-check gearbox torque ratings.

Quick FAQ

What formula is used?
It converts between torque, rotational speed, and power using the standard relationship between angular velocity and torque.

Does it include gearbox or belt losses?
No. The calculation is ideal; apply efficiency or service factors separately when sizing motors, couplings, or drives.

Which units should I watch most closely?
Make sure torque, speed, and power units match the selected fields. Mixing rpm, rad/s, N.m, lbf.ft, kW, and horsepower is the most common source of wrong results.

Can I use the output for final drive selection?
Use it for quick sizing and comparison, then verify against duty cycle, starting torque, shock loads, thermal limits, and manufacturer ratings.