Tire Size Converter
Decode tire sizes like 205/55R16 into diameter, sidewall and revolutions per mile.
–Overall diameter
–Sidewall height
–Circumference
–Revs / mile
How to use
Type a tire size (e.g. 205/55R16) — full dimensions appear; everything runs in your browser.
Frequently asked questions
What does 205/55R16 mean?
205 mm wide, sidewall 55% of width, Radial, fits a 16-inch wheel.
Why does diameter matter?
A different overall diameter changes your speedometer reading and gearing.
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