Tire Size Calculator

Enter a tire size to calculate its dimensions. Accepts formats like 225/65R17, 225-65-17, or 225 65 17.

Format: width/aspect/wheel (e.g., 225/65R17)
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How it works

The tire size calculator uses these formulas:

  • Sidewall height (mm) = Width (mm) × Aspect Ratio / 100
  • Overall diameter (in) = (Wheel diameter × 25.4) + 2 × Sidewall height / 25.4
  • Circumference (in) = Overall diameter × π
  • Revolutions per mile = 63,360 / Circumference

Results are estimates based on nominal dimensions. Actual tire dimensions vary by brand, model, and wear. Use these numbers as a reference only.