About the Wheel Circumference Calculator
Wheel circumference from tyre size (e.g. 700×25c or 26×2.0) for bike computers and cadence maths.
Also known as: tire circumference, wheel size calculator, bike computer wheel size, rollout.
How to use this calculator
- Enter rim diameter (mm), tyre width (mm).
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
C = π × (rim diameter + 2 × tyre width)
Worked example
Using the values pre-filled in the calculator above:
- Rim diameter (mm) = 622
- Tyre width (mm) = 25
the calculator returns:
- Circumference: 2,111 mm
- Diameter: 672 mm
- Circumference (m): 2.111
- Revolutions per km: 473.7