How it works

TireFlows

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Result

Diameter

31.91"

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

255/60R20+0.43%295/50R20-0.93%265/55R20-1.36%285/55R20+1.36%265/60R20+1.91%285/50R20-2.16%255/55R20-2.71%295/55R20+2.71%
Width 10.83 ″Rim 20 ″Dia. 31.91 ″5.95 ″Revs/Mile 632.0Circum. 100.2″
Diameter31.91"
Width10.83"
Sidewall5.95"
Circum.100.246"
Revs/Mile632

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