Tyres
Tyre Size Calculator
Compare validated width, aspect ratio and rim diameter values. Diameter similarity alone does not establish safe fitment.
Calculate your estimate
Results
Enter your details and select Calculate. Results stay in this browser.
How this calculator works
Sidewall is width times aspect ratio. Overall diameter adds two sidewalls to rim diameter; circumference is π times diameter, and rev/km is 1,000,000 divided by circumference.
Checked example
The speed example multiplies indicated speed by proposed diameter divided by original diameter.
Assumptions and privacy
All calculations run locally in your browser. WheelMela does not save or transmit calculator inputs. Results depend on your inputs and should be treated as planning estimates.
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