How to use the Tire Circumference Calculator

Calculate approximate overall tire diameter, circumference and revolutions per mile.

Calculation formula

Overall tire diameter (in) = rim diameter + 2 × section width(mm) × aspect% ÷ 25.4; circumference = π × diameter.

Recommended steps

1. Enter values using the units shown beside each field.
2. Review whether the example assumptions match your situation.
3. Run the calculator and compare the key metrics.
4. Use the source data or official rates when precision matters.

Known limitations

Nominal unloaded tire dimensions; actual rolling circumference varies with load, tire construction, wear and inflation.