245/40R20 tire size

A 245/40R20 tire is 245 mm wide with a sidewall 40% of its width (98.0 mm), fits a 20-inch rim and has an overall diameter of 704 mm (27.7 in).

DimensionMetricImperial
Section width245 mm9.65 in
Sidewall height98.0 mm3.86 in
Rim diameter508.0 mm20 in
Overall diameter704.0 mm27.72 in
Circumference2,211.7 mm87.07 in
Revolutions452 per km728 per mile

Reading the size 245/40R20

245Width in mm40Aspect 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 245/40R20

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
225/55R18705 mm+0.1%100.1Compare
245/45R19703 mm-0.1%99.9Compare
225/60R17702 mm-0.3%99.7Compare
215/70R16707 mm+0.5%100.5Compare
215/65R17711 mm+1.0%101.0Compare
235/65R16712 mm+1.1%101.1Compare
235/60R17714 mm+1.4%101.4
235/45R19694 mm-1.4%98.6

Compare 245/40R20 with any size →

Other 20-inch sizes

245/35R20245/45R20245/50R20255/35R20255/45R20255/50R20265/50R20275/40R20275/45R20275/55R20275/60R20275/65R20