275/45R20 tire size

A 275/45R20 tire is 275 mm wide with a sidewall 45% of its width (123.8 mm), fits a 20-inch rim and has an overall diameter of 756 mm (29.7 in).

DimensionMetricImperial
Section width275 mm10.83 in
Sidewall height123.8 mm4.87 in
Rim diameter508.0 mm20 in
Overall diameter755.5 mm29.74 in
Circumference2,373.5 mm93.44 in
Revolutions421 per km678 per mile

Reading the size 275/45R20

275Width in mm45Aspect ratio (sidewall % of width)RRadial construction20Rim diameter in inches

The load index and speed rating (for example 91V) follow the size on the sidewall. Replacement tires should match or exceed the original load index and speed rating.

Alternative sizes within 3% of 275/45R20

A replacement size should stay within about 3% of the original diameter so the speedometer, ABS and transmission stay accurate. Always check clearance, load index and the vehicle manufacturer's approved sizes.

SizeDiameterDifferenceSpeedo reads 100 → actual
245/50R20753 mm-0.3%99.7Compare
245/60R18751 mm-0.6%99.4Compare
245/65R17750 mm-0.7%99.3Compare
245/70R16749 mm-0.8%99.2Compare
235/65R18763 mm+1.0%101.0Compare
255/50R20763 mm+1.0%101.0Compare
255/55R19763 mm+1.0%101.0Compare
255/60R18763 mm+1.0%101.0Compare

Compare 275/45R20 with any size →

Other 20-inch sizes