How it works

TireFlows

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Result

Diameter

31.61"

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

275/55R20+0.93%285/50R20-1.25%305/50R20+1.25%315/45R20-1.43%285/55R20+2.3%275/50R20-2.49%315/50R20+2.49%305/45R20-2.55%
Width 11.61 ″Rim 20 ″Dia. 31.61 ″5.81 ″Revs/Mile 637.9Circum. 99.3″
Diameter31.61"
Width11.61"
Sidewall5.81"
Circum.99.319"
Revs/Mile637.9

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