How it works

TireFlows

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Result

Diameter

27.74"

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

205/60R18-0.21%245/50R18-0.35%215/60R18+1.49%215/55R18-1.56%235/55R18+1.56%235/50R18-1.77%205/65R18+2.7%
Width 8.86 ″Rim 18 ″Dia. 27.74 ″4.87 ″Revs/Mile 726.9Circum. 87.2″
Diameter27.74"
Width8.86"
Sidewall4.87"
Circum.87.161"
Revs/Mile726.9

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