How it works

TireFlows

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Result

Diameter

32.78"

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

275/60R20+0.66%315/50R20-1.14%285/55R20-1.32%305/55R20+1.32%285/60R20+2.1%305/50R20-2.34%275/55R20-2.64%315/55R20+2.64%
Width 11.61 ″Rim 20 ″Dia. 32.78 ″6.39 ″Revs/Mile 615.3Circum. 103.0″
Diameter32.78"
Width11.61"
Sidewall6.39"
Circum.102.968"
Revs/Mile615.3

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