How it works

TireFlows

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Result

Diameter

29.04"

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

235/50R20+0.75%245/45R20-1.22%265/45R20+1.22%275/40R20-1.29%245/50R20+2.1%265/40R20-2.37%235/45R20-2.44%275/45R20+2.44%
Width 10.04 ″Rim 20 ″Dia. 29.04 ″4.52 ″Revs/Mile 694.6Circum. 91.2″
Diameter29.04"
Width10.04"
Sidewall4.52"
Circum.91.218"
Revs/Mile694.6

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