Engine RPM Calculator

Calculate RPM from speed or speed from RPM.

MPH
1.0 for direct drive (top gear)
inches

Quick RPM Reference @ 70 MPH

Final Drive28" Tire30" Tire
2.73:12,0501,910
3.08:12,3102,160
3.55:12,6602,490
3.73:12,8002,610
4.10:13,0702,870