Use our simple Gear Ratio Calculator to quickly find the correct gear ratio for your ring and pinion gear set.

Save yourself the headache and let us figure out your ring-and-pinion gear ratio!
Select the value you want to solve for.
For the Tire field, enter your tire diameter in inches. If you know your gear ratio then this doubles as a Vehicle Speed Calculator
Just type in your info, press calculate, and you’ll get the right gear ratio without the guesswork.

gear ratio calculator
Click the button for unit you want to solve for.
Gear Ratio (ex. 4.10)
RPM (ex. 6000)
Tire Diameter (in.) (ex. 28)
MPH (ex. 115)
*** Calculated using a 1:1 final drive ratio (No Overdrive)

US GEAR Strange Engineering