Tire & Wheel Calculators
Tire Size Tools

Tire Size to Millimeters

Tire Size to Millimeters. Decode, calculate and compare nominal tire dimensions. Calculations run in your browser; entered tire and wheel values are not uploaded.

Inputs
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Calculations run in your browser; entered tire and wheel values are not uploaded.
ⓘCalculated dimensions are nominal values based on tire-size notation; actual measured dimensions vary. These calculators compare nominal tire and wheel geometry. Actual fitment depends on the vehicle, wheel, tire model, suspension, brake clearance, load/speed ratings and local requirements. Verify final fitment before purchase or installation.

Formula & method

Decode the tire notation and express nominal geometry in millimeters.

Example

225/45R17 → 431.8 mm rim and 634.3 mm overall diameter.

Limitations

Calculated dimensions are nominal values based on tire-size notation; actual measured dimensions vary. These calculators compare nominal tire and wheel geometry. Actual fitment depends on the vehicle, wheel, tire model, suspension, brake clearance, load/speed ratings and local requirements. Verify final fitment before purchase or installation.