255/70R18 tire size

A 255/70R18 tire is 32.06 in (814.2 mm) tall and 10.04 in (255.0 mm) wide, and turns 629 revolutions per mile.

255/70R18 dimensions
MeasurementInchesMillimeters
Overall diameter32.06 in814.2 mm
Section width10.04 in255.0 mm
Sidewall height7.03 in178.5 mm
Rim diameter18.00 in457.2 mm
Circumference100.70 in2,558 mm
Revolutions per mile629
Flotation equivalent32.1x10.0R18 (approx.)

255/70R18 is a 18-inch tire with a 255 mm (10.04 in) section width and a 70% aspect ratio, giving a 7.03-inch sidewall and a flotation-style size of about 32.1x10.0R18.

Its overall diameter is 32.06 inches, so it rolls 100.7 inches per revolution and turns about 629 times per mile.

45 other sizes in this list are within 3% of that diameter.

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Sizes within 3% of 32.06 in diameter

Open 255/70R18 in the tire size calculator

Source: Calculated from standard tire geometry formulas. Verified . How these numbers are calculated.