GREYSUN ENGINEERING TOOL
Pulley Size Calculator
Calculate the required driver pulley diameter from a known driven pulley, motor speed, and either desired output speed or speed ratio.
RPM
RPM
: 1
A ratio of 1.75 means the output speed is 1.75 times the motor speed.
Required Driver Pulley
—
pulley diameter
Enter the driven pulley diameter, motor RPM, and desired output speed.
Formula Used
Driver Pulley = Driven Pulley × Desired Output RPM ÷ Motor RPM
Using a Speed Ratio
Driver Pulley = Driven Pulley × Speed Ratio. A ratio above 1 increases speed; a ratio below 1 decreases speed.
Important Note
Results are theoretical. Actual operating speed may vary due to belt slip, pulley pitch diameter, motor load, and equipment conditions.
Need Help Selecting the Right Pulley?
Greysun can help evaluate motor speed, pulley ratios, equipment speed, belt-drive selection, and centrifuge operating requirements.