Tire size calculator

Current tire size


/ R

New tire size


/ R

Tire size conversion

Old New Diff %
Overall Diameter - - - -
Width - - - -
Sidewall Height - - - -
Rim Diameter - - - -
Ground Clearance
Circumference - - - -

Welcome to our handy wheel and tire size calculator!

Put your current tire size(width, aspect ratio, and diameter) into the first form, then your desired size into the second form and you will get the difference between the new and tire size. Also, determine the speedometer reading difference and the actual speed with a new set of tires. You can use both metric and flotation sizes for your vehicle.

Our tire calculator could help decide whether tires and wheels will fit into your car. If you need to compare tires by brand and model use our tire comparison tool.

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