255/55R18 tire size

A 255/55R18 tire is 29.04 in (737.7 mm) tall and 10.04 in (255.0 mm) wide, and turns 694 revolutions per mile.

• 29.04 inOverall diameter
• 5.52 inSidewall height
• 694Revolutions per mile
• 29.0x10.0R18Flotation equivalent

255/55R18 is a 18-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 29.0x10.0R18.

Its overall diameter is 29.04 inches, so it rolls 91.2 inches per revolution and turns about 694 times per mile.

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

Compare 255/55R18 with plausible swaps

• 215/75R16 vs 255/55R18 (−1.19%)
• 235/70R16 vs 255/55R18 (−0.31%)
• 255/65R16 vs 255/55R18 (+0.03%)
• 225/75R16 vs 255/55R18 (+0.84%)
• 245/70R16 vs 255/55R18 (+1.59%)
• 235/65R17 vs 255/55R18 (−0.05%)
• 255/60R17 vs 255/55R18 (+0.01%)
• 255/50R18 vs 255/55R18 (−3.46%)
• 235/55R18 vs 255/55R18 (−2.98%)
• 245/55R18 vs 255/55R18 (−1.49%)
• 255/55R18 vs 235/60R18 (+0.20%)
• 255/55R18 vs 275/55R18 (+2.98%)
• 255/55R18 vs 255/60R18 (+3.46%)
• 255/55R18 vs 225/55R19 (−1.03%)
• 255/55R18 vs 275/45R19 (−1.03%)
• 255/55R18 vs 255/50R19 (−0.01%)
• 255/55R18 vs 285/45R19 (+0.19%)
• 255/55R18 vs 235/55R19 (+0.46%)
• 255/55R18 vs 285/40R20 (−0.23%)
• 255/55R18 vs 255/45R20 (−0.03%)
• 255/55R18 vs 295/40R20 (+0.85%)

Sizes within 3% of 29.04 in diameter

• 255/60R17 29.05 in (+0.01%)
• 255/50R19 29.04 in (−0.01%)
• 255/65R16 29.05 in (+0.03%)
• 255/45R20 29.04 in (−0.03%)
• 255/70R15 29.06 in (+0.04%)
• 255/40R21 29.03 in (−0.04%)
• 235/65R17 29.03 in (−0.05%)
• 255/35R22 29.03 in (−0.05%)
• 285/45R19 29.10 in (+0.19%)
• 235/60R18 29.10 in (+0.20%)
• 285/40R20 28.98 in (−0.23%)
• 295/30R22 28.97 in (−0.26%)
• 295/35R21 29.13 in (+0.30%)
• 235/70R16 28.95 in (−0.31%)
• 235/55R19 29.18 in (+0.46%)
• 235/75R15 28.88 in (−0.57%)
• 285/35R21 28.85 in (−0.65%)
• 225/75R16 29.29 in (+0.84%)
• 295/40R20 29.29 in (+0.85%)
• 265/35R22 29.30 in (+0.89%)
• 235/45R21 29.33 in (+0.98%)
• 245/35R22 28.75 in (−1.00%)
• 225/55R19 28.74 in (−1.03%)
• 275/45R19 28.74 in (−1.03%)
• 265/40R21 29.35 in (+1.04%)
• 285/30R22 28.73 in (−1.07%)
• 245/40R21 28.72 in (−1.13%)
• 265/45R20 29.39 in (+1.19%)
• 215/75R16 28.70 in (−1.19%)
• 245/45R20 28.68 in (−1.25%)
• 315/35R20 28.68 in (−1.25%)
• 325/30R21 28.68 in (−1.26%)
• 275/25R24 29.41 in (+1.27%)
• 275/40R20 28.66 in (−1.31%)
• 265/50R19 29.43 in (+1.34%)
• 315/30R22 29.44 in (+1.37%)
• 245/50R19 28.65 in (−1.37%)
• 225/60R18 28.63 in (−1.42%)
• 245/75R15 29.47 in (+1.46%)
• 245/55R18 28.61 in (−1.49%)
• 245/70R16 29.50 in (+1.59%)
• 275/35R21 28.58 in (−1.60%)
• 245/60R17 28.57 in (−1.61%)
• 265/60R17 29.52 in (+1.64%)
• 245/65R17 29.54 in (+1.71%)
• 245/65R16 28.54 in (−1.74%)
• 225/65R17 28.52 in (−1.82%)
• 245/60R18 29.57 in (+1.83%)
• 275/30R22 28.50 in (−1.88%)
• 265/70R15 29.61 in (+1.94%)
• 305/40R20 29.61 in (+1.94%)
• 245/55R19 29.61 in (+1.95%)
• 245/50R20 29.65 in (+2.07%)
• 265/50R18 28.43 in (−2.10%)
• 275/40R21 29.66 in (+2.13%)
• 245/45R21 29.68 in (+2.20%)
• 315/35R21 29.68 in (+2.20%)
• 225/70R16 28.40 in (−2.21%)
• 265/45R19 28.39 in (−2.25%)
• 265/40R20 28.35 in (−2.40%)
• 275/45R20 29.74 in (+2.41%)
• 235/45R20 28.33 in (−2.47%)
• 265/35R21 28.30 in (−2.55%)
• 295/40R19 28.29 in (−2.59%)
• 225/75R15 28.29 in (−2.60%)
• 275/50R19 29.83 in (+2.70%)
• 265/30R22 28.26 in (−2.70%)
• 235/50R19 28.25 in (−2.72%)
• 285/35R22 29.85 in (+2.79%)
• 235/75R16 29.88 in (+2.87%)
• 305/30R21 28.20 in (−2.89%)
• 235/55R18 28.18 in (−2.98%)
• 275/55R18 29.91 in (+2.98%)

Open 255/55R18 in the tire size calculator

Source: Calculated from standard tire geometry formulas. Verified 2026-09-27. How these numbers are calculated.