255/55R20 tire size

A 255/55R20 tire is 31.04 in (788.5 mm) tall and 10.04 in (255.0 mm) wide, and turns 650 revolutions per mile.

255/55R20 dimensions
MeasurementInchesMillimeters
Overall diameter31.04 in788.5 mm
Section width10.04 in255.0 mm
Sidewall height5.52 in140.3 mm
Rim diameter20.00 in508.0 mm
Circumference97.53 in2,477 mm
Revolutions per mile650
Flotation equivalent31.0x10.0R20 (approx.)

255/55R20 is a 20-inch tire with a 255 mm (10.04 in) section width and a 55% aspect ratio, giving a 5.52-inch sidewall and a flotation-style size of about 31.0x10.0R20.

Its overall diameter is 31.04 inches, so it rolls 97.5 inches per revolution and turns about 650 times per mile.

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

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Sizes within 3% of 31.04 in diameter

Open 255/55R20 in the tire size calculator

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