Decoded notation
255 mm / 50% / R / 21 in
Popular Tire Sizes
255/50R21 Tire Size — Dimensions & Revs
Decode 255/50R21 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 diameter21 in
Overall diameter788.4 mm
Overall diameter31.04 in
Circumference2476.8 mm
Revolutions per mile649.8
Revolutions per km403.7