4 reference tools
Belt & Pulley Calculators: Length, Speed & Ratio
Calculate V-belt datum length, timing-belt pitch length and tooth count, pulley speed ratio, belt speed, or pulley RPM with explicit diameter conventions.
Which belt length or pulley speed tool fits your drive?
Use the V-belt tool for approximate datum-length geometry and the timing-belt tool for synchronous pitch length and whole tooth count. Use pulley ratio to relate two pulley speeds, or belt speed to connect one reference diameter with RPM. Keep the diameter and length conventions consistent. These tools calculate geometry or ideal speed; belt power rating, tension, width, and catalog selection require separate evidence.
Choose a calculator
- #010
V-Belt Length / Center Distance Calculator
Calculate approximate V-belt datum length from pulley diameters and center distance, or solve center distance from a known datum length.
- #011
Belt Speed / Pulley RPM Calculator
Calculate belt speed from pulley diameter and RPM, or solve pulley RPM from belt speed using metric or imperial units.
- #012
Pulley Speed Ratio / Driven RPM Calculator
Calculate driven pulley RPM, pulley speed ratio, speed multiplier, and ideal belt speed from two pulley diameters and driver RPM.
- #013
Timing Belt Length / Center Distance Calculator
Calculate exact timing belt pitch length, whole belt tooth count, center distance, pitch diameters, wrap angle, and teeth in mesh.
Before you use the result
- Identify whether the drive is an open V-belt or synchronous-belt arrangement, then choose its corresponding length model.
- Use datum or pitch-line dimensions as requested. Outside diameter and outside belt length are not automatic substitutes.
- After choosing an available catalog belt, recalculate center distance and review wrap, installation adjustment, tension, and the manufacturer rating method.
Each linked tool includes its own formulas, worked examples, input units, limitations, and source notes. See how MechClarity documents and checks its calculations.
Continue with related calculations
- Power, Torque & RPM Calculator and Drive Tools — Convert between shaft power, torque, and rotational speed in SI or imperial units, then continue to gear, pulley, shaft, and bearing calculations.
- Shaft Calculators: Stress, Deflection & Critical Speed — Calculate shaft torsion, diameter, bending stress, bearing reactions, deflection, critical speed, key stress, and rigid flange coupling loads.
- Roller Chain Calculator: Links & Center Distance — Estimate roller-chain length and whole link count for an open two-sprocket drive, then check the center distance after choosing a link count.