Speed Ratio Calculator

MECHANICAL

Driver / Driven · Pulleys · Gears · Belts · RPM conversion

SR = N₁ / N₂ SR = D₂ / D₁

Enter any two values — the rest will be calculated

Driver speed (N₁)

RPM

Driven speed (N₂)

RPM

Driver diameter (D₁) or teeth

Driven diameter (D₂) or teeth

                        Speed Ratio (N₁ / N₂)
                        —
                        :1
                    

Diameter Ratio (D₂ / D₁) — :1

Speed change — %

Type — —

SR = N₁ / N₂ = D₂ / D₁

Driver speed vs Driven speed

Driver

50%

Driven

100%