Using our free online tire size calculator, you can calculate current and new tire overall diameter, tread width, circumference, sidewall height, mileage and km, rim size, radius/ground clearance, ground clearance changes, and speed changes. Using this tool, you can determine if your new tires can be used on your car, SUV, or truck.

Select your old and new tire sizes using this tool drop-down menu and click the “Calculate” button to get the result.


Old Tire Size

/ R
/ R

New Tire Size

Parameter Old Tire New Tire Difference
Overall diameter:
Section width:
Sidewall height:
Revs per km:
Rim size:
Radius/Ground Clearance:
Ground Clearance Change:
Diameter Difference %
New Tires Actual Speed (Old tires @60MPH)
Speedometer Difference at 60MPH
Can Replace New Tire