Tire Size Calculator

Enter a size such as 225/65R17 or 33x12.50R15 and calculate its theoretical dimensions locally.

Tire size

—Overall diameter

—Section width

—Sidewall height

—Revolutions / mile

—Theoretical dimensions; actual manufactured tires vary by model, load, pressure, and rim width.

How to use this Tire Size Calculator

Calculate tire diameter, sidewall, circumference, width, and revolutions per mile from a metric or flotation tire size. Enter your values above and the result is calculated directly in your browser. No account is required.

Fast answer, clear inputs

This tool is built around one job: give the answer quickly without forcing a signup or hiding the result. Related tools are linked nearby when the next calculation or conversion is useful.