Earth Bondhon
Creators
Md Jony Islam Author
Md Jony Islam
CalculatorToolsProjectExpert
Reviewers
Małgorzata Koperska, MD Steven Wooding
Last updated: October 26, 2025

Speed to Power Calculator | Convert RPM & Torque to Watts/HP

🇺🇸
English
Default
🇪🇸
Español
Spanish
🇫🇷
Français
French
🇩🇪
Deutsch
German

Speed to Power Calculator

Instantly convert rotational speed (RPM) and torque to mechanical power in watts, kilowatts, or horsepower using this Speed to Power Calculator.

speed to power calculator:

The Speed to Power Calculator takes a short time to convert rotational speed (RPM) and torque into mechanical power output. It is perfect for the analysis of motors, pumps, and other rotating machines. This calculator is useful when you are designing systems, verifying performance, or estimating the energy consumption, and it is capable of giving instant and accurate results. It works with various power units, which allows it to be used in industrial, automotive, and scholarly contexts.

speed to power tool Formula:

To calculate the mechanical power output of rotating machines (motor, pump, and turbine), the Calculator or Speed to Power is useful. The calculator uses the torque and rotational speed (RPM) to calculate the power in watts, kilowatts, or horsepower.
The main formula is:

\[ Power(W) = \frac{\textrm{Torque (Nm)} \times \textrm{Speed (RPM)}}{9.5488} \]

You can also convert power to horsepower using:

\[ Power(HP) = \frac{\textrm{Torque (Nm)} \times \textrm{Speed (RPM)}}{7127} \]

The device is needed by the engineers and mechanics to know the efficiency of machines, their performance, and the capacity of load-bearing capacity. It makes the sizing of motors, energy auditing, and mechanical design analysis easy.

Work & Installation — Input to Output Summary

Power: Enter rotational speed (RPM) and torque (Nm or lb-ft). The calculator uses standard mechanical power equations to yield the results in watts, kilowatts, or horsepower. The process demonstrates the relationship between torque and speed in order to calculate the actual mechanical power output. This conversion can be used in the analysis of motor performance or to choose the appropriate gear ratio, or it can be applied to assess efficiency within the mechanical systems between the input speed and the final power output.

Testing and Final Adjustments

Calculate and check the results with the help of a dynamometer or torque meter. Compare the values of measured torque and RPM with the calculator's values to test whether these are the desired performance in your system. Tune the frictional losses, gear efficiency, and alignment to make the maximum power. Measurement assists in proper calibration, which guarantees the work of the machine, avoids overloading, and prolongs the service of the equipment. Frequent testing enables balancing the optimum torque-speed relationship to achieve efficiency when in use in industrial and automotive setups.

Frequently Asked Questions - Speed to Power Calculator:

What is the formula for converting speed to power?

Power (W) = (Torque (Nm) × Speed (RPM)) / 9.5488.

How do I convert RPM and torque to horsepower?

Use Power (HP) = (Torque (Nm) × RPM) / 7127.

What is mechanical power?

Mechanical power is the rate at which work is done by a rotating shaft or component.

Can I use lb-ft for torque?

Yes, the calculator supports both Nm and lb-ft torque units.

What units does the calculator output?

It provides power in watts, kilowatts, and horsepower.

Is this calculator useful for electric motors?

Yes, it helps determine power output for motors and rotating machines.

How accurate are the results?

Results are highly accurate when torque and speed are measured precisely.

What does RPM mean?

RPM stands for revolutions per minute, representing rotational speed.

Can this be used for turbine analysis?

Yes, it’s ideal for turbines, compressors, and similar rotating systems.

Why is 9.5488 used in the formula?

It’s the constant for converting torque × RPM into watts.

Md Jony Islam

Md Jony Islam

CalculatorToolsProject

Founder of Earthbondhon.com

a free online tools website designed to make everyday and engineering-related calculations easier for students, professionals, and hobbyists. The site offers a wide range of basic calculators across key categories, including Electrical Calculators, Electronic Calculators, and Time & Date Calculators.