275/70R18 tire size

A 275/70R18 tire is 275 mm wide with a sidewall 70% of its width (192.5 mm), fits a 18-inch rim and has an overall diameter of 842 mm (33.2 in).

DimensionMetricImperial
Section width275 mm10.83 in
Sidewall height192.5 mm7.58 in
Rim diameter457.2 mm18 in
Overall diameter842.2 mm33.16 in
Circumference2,645.8 mm104.17 in
Revolutions378 per km608 per mile

Reading the size 275/70R18

275Width in mm70Aspect ratio (sidewall % of width)RRadial construction18Rim 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 275/70R18

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
275/60R20838 mm-0.5%99.5Compare
285/75R16834 mm-1.0%99.0Compare
285/70R17831 mm-1.4%98.6Compare
265/70R18828 mm-1.7%98.3Compare
275/65R20866 mm+2.8%102.8Compare

Compare 275/70R18 with any size →

Other 18-inch sizes