Engineering Tool
Belt Speed & RPM Calculator
Enter your driver RPM and both pulley diameters to find the driven shaft speed and the belt's linear speed — in both metric (m/s) and imperial (ft/min).
Units:
How belt speed is calculated
The driven shaft speed is set by the ratio of the pulley diameters. A smaller driven pulley spins faster than the driver:
Driven RPM = Driver RPM × (Driver Ø ÷ Driven Ø)
The belt's linear speed is the circumference of the driver pulley multiplied by how often it rotates each second:
Belt speed (m/s) = π × Driver Ø (m) × RPM ÷ 60
Belt speed matters for selecting the right belt construction — high surface speeds need belts rated for the flex rate and heat generated. Use Get a price to send your numbers to our team.