How it works

TireFlows

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Result

Diameter

27.25"

Calculated from size marking (math only) — not a fitment guarantee. How it works

Alternate Tire Sizes

Closest diameters (math only · same rim · within 3%)

Tap a size to compare it with your current size

215/55R18+0.22%255/45R18-0.79%225/50R18-1.44%245/50R18+1.44%225/55R18+1.81%245/45R18-2.09%215/50R18-2.89%255/50R18+2.89%
Width 9.25 ″Rim 18 ″Dia. 27.25 ″4.63 ″Revs/Mile 740.1Circum. 85.6″
Diameter27.25"
Width9.25"
Sidewall4.63"
Circum.85.615"
Revs/Mile740.1

How results are calculated

Tire dimensions are calculated from the metric size format (width / aspect ratio / rim diameter). Diameter, circumference, and revolutions per mile are derived mathematically — no fitment or vehicle data is used.

The 3% rule is a general reference for acceptable diameter difference, not a guarantee. Always check your vehicle manual or consult a tire professional.

How it works