How it works

TireFlows

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Result

Diameter

29.48"

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

245/60R18+0.33%285/50R18-0.87%255/55R18-1.47%275/55R18+1.47%255/60R18+1.94%275/50R18-2.2%245/55R18-2.94%285/55R18+2.94%
Width 10.43 ″Rim 18 ″Dia. 29.48 ″5.74 ″Revs/Mile 684.2Circum. 92.6″
Diameter29.48"
Width10.43"
Sidewall5.74"
Circum.92.603"
Revs/Mile684.2

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