How it works

TireFlows

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Result

Diameter

26.68"

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

225/50R18+0.66%265/40R18-1.25%235/45R18-1.33%255/45R18+1.33%235/50R18+2.14%255/40R18-2.43%225/45R18-2.66%265/45R18+2.66%
Width 9.65 ″Rim 18 ″Dia. 26.68 ″4.34 ″Revs/Mile 755.9Circum. 83.8″
Diameter26.68"
Width9.65"
Sidewall4.34"
Circum.83.821"
Revs/Mile755.9

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