Pulley Ratio Calculator
Calculate driven pulley speed from pulley diameters and driver speed.
Result
About this calculator
Calculate driven pulley speed from pulley diameters and driver speed.
Enter valid values, choose the units you need, then select Calculate. The calculation runs in your browser and does not require an account.
How to use this calculator
What to enter
Enter or select the following as requested: Driver pulley diameter; Driven pulley diameter; Driver speed (rpm); Result unit. Follow the units, valid ranges, examples, and options displayed beside each field.
What the result means
The numerical result follows the operation or relationship named by the calculator and the values entered. Check the order of operations, sign, precision, and units shown, especially when combining percentages or ratios.
When to use it
Use this to calculate or verify a numerical value. Recheck the input values and rounding if the result will be used in a report, measurement, or further calculation.