Tire Size Calculator

Compare original and new tire sizes (e.g. 265/70R17). See overall diameter, circumference, and speedometer error.

Enter Details

Original tire

Width (mm)

Aspect (%)

Rim (in)

e.g. 265/70R17

New tire

Width (mm)

Aspect (%)

Rim (in)

e.g. 275/65R17

Enter original and new tire sizes to compare diameter and speedometer effect.

Metric tire sizing (e.g. 265/70R17). Actual rolling diameter can vary by brand and load.