Engine RPM Calculator

Estimate engine RPM from vehicle speed, tire diameter, axle ratio and transmission ratio.

Estimated result

How this calculator works

Estimate engine RPM from vehicle speed, tire diameter, axle ratio and transmission ratio.

RPM = MPH × Axle ratio × Transmission ratio × 336 ÷ Tire diameter

Planning note

Results are estimates. Confirm vehicle ratings, tire specifications and manufacturer guidance before making safety-critical decisions.