Engineering

Gear Ratio Calculator

Ratio, output speed and torque.

Enter your values

Results update instantly as you type — no submit needed.

Results
Gear ratio
3:1
Output speed
583 rpm
Output torque
36 Nm
Mechanical advantage
3

Quick answer

Gear ratio is driven teeth divided by driving teeth; it trades speed for torque.

Ratio = driven teeth ÷ driving teeth

How to use the Gear Ratio Calculator

  1. 1Enter the tooth count of both gears.
  2. 2Enter input speed and torque.
  3. 3Read the output speed and torque.

Frequently asked questions

Does a gearbox create power?

No — torque rises only as speed falls, minus friction losses.

What is overdrive?

A ratio below 1:1, which raises speed and reduces torque.