225/55R18 tire size

A 225/55R18 tire is 27.74 in (704.7 mm) tall and 8.86 in (225.0 mm) wide, and turns 727 revolutions per mile.

225/55R18 dimensions
MeasurementInchesMillimeters
Overall diameter27.74 in704.7 mm
Section width8.86 in225.0 mm
Sidewall height4.87 in123.8 mm
Rim diameter18.00 in457.2 mm
Circumference87.16 in2,214 mm
Revolutions per mile727
Flotation equivalent27.7x8.9R18 (approx.)

225/55R18 is a 18-inch tire with a 225 mm (8.86 in) section width and a 55% aspect ratio, giving a 4.87-inch sidewall and a flotation-style size of about 27.7x8.9R18.

Its overall diameter is 27.74 inches, so it rolls 87.2 inches per revolution and turns about 727 times per mile.

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

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Sizes within 3% of 27.74 in diameter

Open 225/55R18 in the tire size calculator

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