Gear Ratio RPM

RPM_out = RPM_in × (T_in / T_out)

How to Use This Calculator

Enter input RPM, driver gear teeth (T_in), and driven gear teeth (T_out). The output RPM is inversely proportional to gear ratio.

Formula

RPM_out = RPM_in × (T_in / T_out)

Frequently Asked Questions

What about compound gear trains?

Multiply stage ratios: overall ratio = Π(T_in,i / T_out,i). Apply the same formula with overall ratio.