255/70R17 tire size

A 255/70R17 tire is 255 mm wide with a sidewall 70% of its width (178.5 mm), fits a 17-inch rim and has an overall diameter of 789 mm (31.1 in).

DimensionMetricImperial
Section width255 mm10.04 in
Sidewall height178.5 mm7.03 in
Rim diameter431.8 mm17 in
Overall diameter788.8 mm31.06 in
Circumference2,478.1 mm97.56 in
Revolutions404 per km649 per mile

Reading the size 255/70R17

255Width in mm70Aspect ratio (sidewall % of width)RRadial construction17Rim 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 255/70R17

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
255/65R18789 mm-0.0%100.0Compare
245/75R17799 mm+1.3%101.3Compare
265/70R16777 mm-1.4%98.6Compare
265/65R17776 mm-1.6%98.4Compare
265/65R18802 mm+1.6%101.6Compare
265/60R18775 mm-1.7%98.3Compare
245/70R17775 mm-1.8%98.2
265/70R17803 mm+1.8%101.8

Compare 255/70R17 with any size →

Other 17-inch sizes