How it works

TireFlows

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Result

Diameter

25.72"

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

225/45R18+1%235/40R18-1.22%255/40R18+1.22%235/45R18+2.37%225/40R18-2.45%265/40R18+2.45%
Width 9.65 ″Rim 18 ″Dia. 25.72 ″3.86 ″Revs/Mile 784.2Circum. 80.8″
Diameter25.72"
Width9.65"
Sidewall3.86"
Circum.80.791"
Revs/Mile784.2

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