How it works

TireFlows

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Result

Diameter

26.86"

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

205/55R18+0.07%245/45R18-0.66%215/50R18-1.47%235/50R18+1.47%215/55R18+1.69%235/45R18-1.98%205/50R18-2.93%245/50R18+2.93%
Width 8.86 ″Rim 18 ″Dia. 26.86 ″4.43 ″Revs/Mile 750.9Circum. 84.4″
Diameter26.86"
Width8.86"
Sidewall4.43"
Circum.84.378"
Revs/Mile750.9

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