Automotive Calculators
Tire Size Calculator
Decode any tire size code to get full dimensions. Enter a code like 215/55R17 or fill in values manually for instant results in both metric and imperial units.
FreeCode ParserMetric & ImperialNo sign-up
Quick Parse from Tire Code
Manual Entry
mm
%
in
Tire Diameter
26.31"
668.3 mm
Sidewall Height
4.66"
118.3 mm
Section Width
8.46"
215 mm
Circumference
82.66"
2099.5 mm
Rev / Mile
767
rotations per mile
Tire size codes follow the format: Width / Aspect Ratio R Rim Diameter. For example, 215/55R17 means 215mm wide, 55% aspect ratio, 17-inch rim.
Understanding Tire Size Codes
Tire sizes are printed on the sidewall and follow a standard format: Width / Aspect Ratio R Rim Diameter. For example:
- 215 — Section width in millimeters
- /55 — Aspect ratio: sidewall height is 55% of the width
- R — Radial construction (standard for modern tires)
- 17 — Rim diameter in inches