325/30R21 tire size

A 325/30R21 tire is 28.68 in (728.4 mm) tall and 12.80 in (325.0 mm) wide, and turns 703 revolutions per mile.

325/30R21 dimensions
MeasurementInchesMillimeters
Overall diameter28.68 in728.4 mm
Section width12.80 in325.0 mm
Sidewall height3.84 in97.5 mm
Rim diameter21.00 in533.4 mm
Circumference90.09 in2,288 mm
Revolutions per mile703
Flotation equivalent28.7x12.8R21 (approx.)

325/30R21 is a 21-inch tire with a 325 mm (12.80 in) section width and a 30% aspect ratio, giving a 3.84-inch sidewall and a flotation-style size of about 28.7x12.8R21.

Its overall diameter is 28.68 inches, so it rolls 90.1 inches per revolution and turns about 703 times per mile.

76 other sizes in this list are within 3% of that diameter.

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Sizes within 3% of 28.68 in diameter

Open 325/30R21 in the tire size calculator

Source: Calculated from standard tire geometry formulas. Verified . How these numbers are calculated.