Decoded notation
255 mm / 50% / R / 18 in
Popular Tire Sizes
255/50R18 Tire Size — Dimensions & Revs
Decode 255/50R18 and calculate nominal width, sidewall, overall diameter, circumference and revolutions.
Calculated dimensions are nominal values based on tire-size notation; actual measured dimensions vary.
Width255 mm
Sidewall height127.5 mm
Rim diameter18 in
Overall diameter712.2 mm
Overall diameter28.04 in
Circumference2237.4 mm
Revolutions per mile719.3
Revolutions per km446.9