Rpm Calculator
Calculate the rotational speed (RPM) of a motor or engine based on frequency and number of poles, or from linear speed and diameter.
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isCalculator Editorial Team
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How to use this tool?
How to Use the RPM Calculator
This calculator computes Revolutions Per Minute (RPM) using two methods. Choose the one that matches your data.
- Select a method from the dropdown: From Frequency & Poles or From Linear Speed & Diameter.
- Enter the required values:
- Frequency & Poles: Enter frequency in Hertz (Hz) and an even number of poles (≥2).
- Linear Speed & Diameter: Enter linear speed in meters per second (m/s) and diameter in meters (m).
- Click Calculate. The RPM result and formula used will appear below.
Note: All inputs must be positive numbers. Use metric units (Hz, m/s, meters). Invalid entries will show a red error border.
Previous Results
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Frequently Asked Questions
RPM stands for revolutions per minute, a measure of rotational speed.
Use the formula: RPM = (120 × Frequency) / Number of Poles.
Use the formula: RPM = (Linear Speed × 60) / (π × Diameter).