How it works

TireFlows

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Result

Diameter

30.83"

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

255/55R20+0.7%295/45R20-1.21%265/50R20-1.28%285/50R20+1.28%265/55R20+2.11%285/45R20-2.36%255/50R20-2.55%295/50R20+2.55%
Width 10.83 ″Rim 20 ″Dia. 30.83 ″5.41 ″Revs/Mile 654.2Circum. 96.8″
Diameter30.83"
Width10.83"
Sidewall5.41"
Circum.96.845"
Revs/Mile654.2

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