How it works

TireFlows

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Result

Diameter

28.63"

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

245/55R18-0.07%205/65R18-0.48%215/65R18+1.31%235/55R18-1.58%215/60R18-1.65%235/60R18+1.65%205/70R18+2.34%
Width 8.86 ″Rim 18 ″Dia. 28.63 ″5.31 ″Revs/Mile 704.4Circum. 89.9″
Diameter28.63"
Width8.86"
Sidewall5.31"
Circum.89.944"
Revs/Mile704.4

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