305/30R21 tire size
A 305/30R21 tire is 28.20 in (716.4 mm) tall and 12.01 in (305.0 mm) wide, and turns 715 revolutions per mile.
- 28.20 inOverall diameter
- 3.60 inSidewall height
- 715Revolutions per mile
- 28.2x12.0R21Flotation equivalent
| Measurement | Inches | Millimeters |
|---|---|---|
| Overall diameter | 28.20 in | 716.4 mm |
| Section width | 12.01 in | 305.0 mm |
| Sidewall height | 3.60 in | 91.5 mm |
| Rim diameter | 21.00 in | 533.4 mm |
| Circumference | 88.61 in | 2,251 mm |
| Revolutions per mile | 715 | |
| Flotation equivalent | 28.2x12.0R21 (approx.) | |
305/30R21 is a 21-inch tire with a 305 mm (12.01 in) section width and a 30% aspect ratio, giving a 3.60-inch sidewall and a flotation-style size of about 28.2x12.0R21.
Its overall diameter is 28.20 inches, so it rolls 88.6 inches per revolution and turns about 715 times per mile.
77 other sizes in this list are within 3% of that diameter.
Compare 305/30R21 with plausible swaps
- 285/40R19 vs 305/30R21 (−0.81%)
- 255/45R19 vs 305/30R21 (−0.60%)
- 235/50R19 vs 305/30R21 (+0.17%)
- 295/40R19 vs 305/30R21 (+0.31%)
- 265/45R19 vs 305/30R21 (+0.66%)
- 255/40R20 vs 305/30R21 (−0.61%)
- 295/35R20 vs 305/30R21 (−0.27%)
- 235/45R20 vs 305/30R21 (+0.43%)
- 265/40R20 vs 305/30R21 (+0.50%)
- 295/30R21 vs 305/30R21 (−0.84%)
- 255/35R21 vs 305/30R21 (−0.63%)
- 305/30R21 vs 265/35R21 (+0.35%)
- 305/30R21 vs 325/30R21 (+1.68%)
- 305/30R21 vs 245/30R22 (−1.48%)
- 305/30R21 vs 295/25R22 (−1.41%)
- 305/30R21 vs 255/30R22 (−0.64%)
- 305/30R21 vs 265/30R22 (+0.20%)
- 305/30R21 vs 275/30R22 (+1.03%)
Sizes within 3% of 28.20 in diameter
- 235/55R18 28.18 in (−0.10%)
- 235/50R19 28.25 in (+0.17%)
- 265/30R22 28.26 in (+0.20%)
- 295/35R20 28.13 in (−0.27%)
- 225/75R15 28.29 in (+0.29%)
- 295/40R19 28.29 in (+0.31%)
- 205/75R16 28.11 in (−0.35%)
- 265/35R21 28.30 in (+0.35%)
- 235/60R17 28.10 in (−0.36%)
- 285/45R18 28.10 in (−0.38%)
- 235/45R20 28.33 in (+0.43%)
- 265/40R20 28.35 in (+0.50%)
- 255/50R18 28.04 in (−0.59%)
- 255/45R19 28.04 in (−0.60%)
- 255/40R20 28.03 in (−0.61%)
- 235/65R16 28.03 in (−0.63%)
- 255/35R21 28.03 in (−0.63%)
- 255/30R22 28.02 in (−0.64%)
- 265/45R19 28.39 in (+0.66%)
- 225/70R16 28.40 in (+0.70%)
- 215/65R17 28.00 in (−0.71%)
- 265/50R18 28.43 in (+0.81%)
- 285/40R19 27.98 in (−0.81%)
- 295/30R21 27.97 in (−0.84%)
- 235/70R15 27.95 in (−0.89%)
- 275/30R22 28.50 in (+1.03%)
- 225/65R17 28.52 in (+1.10%)
- 245/65R16 28.54 in (+1.19%)
- 225/50R19 27.86 in (−1.23%)
- 285/35R20 27.85 in (−1.24%)
- 215/70R16 27.85 in (−1.26%)
- 245/60R17 28.57 in (+1.31%)
- 275/35R21 28.58 in (+1.33%)
- 295/25R22 27.81 in (−1.41%)
- 245/55R18 28.61 in (+1.44%)
- 245/30R22 27.79 in (−1.48%)
- 225/60R18 28.63 in (+1.51%)
- 245/50R19 28.65 in (+1.56%)
- 245/35R21 27.75 in (−1.61%)
- 275/40R20 28.66 in (+1.62%)
- 225/55R18 27.74 in (−1.63%)
- 275/45R18 27.74 in (−1.63%)
- 325/30R21 28.68 in (+1.68%)
- 245/45R20 28.68 in (+1.69%)
- 315/35R20 28.68 in (+1.69%)
- 245/40R20 27.72 in (−1.73%)
- 215/75R16 28.70 in (+1.74%)
- 215/75R15 27.70 in (−1.80%)
- 245/40R21 28.72 in (+1.81%)
- 245/45R19 27.68 in (−1.86%)
- 285/30R22 28.73 in (+1.87%)
- 225/55R19 28.74 in (+1.91%)
- 275/45R19 28.74 in (+1.91%)
- 275/40R19 27.66 in (−1.93%)
- 245/35R22 28.75 in (+1.94%)
- 245/50R18 27.65 in (−1.98%)
- 225/60R17 27.63 in (−2.04%)
- 245/55R17 27.61 in (−2.11%)
- 275/35R20 27.58 in (−2.22%)
- 245/60R16 27.57 in (−2.23%)
- 285/35R21 28.85 in (+2.30%)
- 235/75R15 28.88 in (+2.39%)
- 225/65R16 27.52 in (−2.44%)
- 275/30R21 27.50 in (−2.51%)
- 235/70R16 28.95 in (+2.65%)
- 295/30R22 28.97 in (+2.71%)
- 285/40R20 28.98 in (+2.74%)
- 305/35R19 27.41 in (−2.83%)
- 225/70R15 27.40 in (−2.85%)
- 265/45R18 27.39 in (−2.89%)
- 235/65R17 29.03 in (+2.92%)
- 255/35R22 29.03 in (+2.92%)
- 255/40R21 29.03 in (+2.93%)
- 255/45R20 29.04 in (+2.95%)
- 255/50R19 29.04 in (+2.96%)
- 255/55R18 29.04 in (+2.97%)
- 255/60R17 29.05 in (+2.99%)
Open 305/30R21 in the tire size calculator
Source: Calculated from standard tire geometry formulas. Verified . How these numbers are calculated.