How it works

TireFlows

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Result

Diameter

30.43"

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

245/55R20+0.58%285/45R20-1.1%255/50R20-1.29%275/50R20+1.29%255/55R20+2.01%275/45R20-2.26%245/50R20-2.59%285/50R20+2.59%
Width 10.43 ″Rim 20 ″Dia. 30.43 ″5.22 ″Revs/Mile 662.7Circum. 95.6″
Diameter30.43"
Width10.43"
Sidewall5.22"
Circum.95.608"
Revs/Mile662.7

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