Pulley Calculator - Centers RPM Belt Length and Speed
Gap Small Pulleys May Touch
Enter Large and Small Pulley Diameters and Pulley Center Distance.
Select RPM Large or RPM Small and enter RPM to calculate corresponding pulley RPM.
Drag sliders or mouse over diagram to animate.
If you know any 3 values (Pulley sizes or RPM) and need to calculate the last one, enter the 3 known values and hit Calculate
to find the missing value. For example, if your small pulley is 6" diameter, and spins at 1000 RPM, and you need to find the second pulley size to spin it at 500 RPM,
Enter Pulley1 Size 6, Pulley 1 RPM 1000, Pulley 2 RPM 500, and hit Calculate to find the second pulley diameter.
Enter inches as decimal or fraction with space or slash. eg: 6.75 or 6 3/4 or 6 3 4
To fine tune Slider Controls click to select and use ◄► (cursor) keyboard keys.
Open new window containing only diagram images in current page. Create PDF files to print.
Your iPad, iPhone or Android Tablet or Phone is a valuable On-Site tool!
Lay your phone or tablet on an angled surface (roof ?) to directly measure angles and automatically calculate Roofing and Pitch Angle Apps.