245/40R21 tire size
A 245/40R21 tire is 28.72 in (729.4 mm) tall and 9.65 in (245.0 mm) wide, and turns 702 revolutions per mile.
- 28.72 inOverall diameter
- 3.86 inSidewall height
- 702Revolutions per mile
- 28.7x9.6R21Flotation equivalent
| Measurement | Inches | Millimeters |
|---|---|---|
| Overall diameter | 28.72 in | 729.4 mm |
| Section width | 9.65 in | 245.0 mm |
| Sidewall height | 3.86 in | 98.0 mm |
| Rim diameter | 21.00 in | 533.4 mm |
| Circumference | 90.22 in | 2,291 mm |
| Revolutions per mile | 702 | |
| Flotation equivalent | 28.7x9.6R21 (approx.) | |
245/40R21 is a 21-inch tire with a 245 mm (9.65 in) section width and a 40% aspect ratio, giving a 3.86-inch sidewall and a flotation-style size of about 28.7x9.6R21.
Its overall diameter is 28.72 inches, so it rolls 90.2 inches per revolution and turns about 702 times per mile.
76 other sizes in this list are within 3% of that diameter.
Compare 245/40R21 with plausible swaps
- 245/50R19 vs 245/40R21 (−0.25%)
- 225/55R19 vs 245/40R21 (+0.10%)
- 275/45R19 vs 245/40R21 (+0.10%)
- 275/40R20 vs 245/40R21 (−0.19%)
- 245/45R20 vs 245/40R21 (−0.12%)
- 315/35R20 vs 245/40R21 (−0.12%)
- 285/40R20 vs 245/40R21 (+0.90%)
- 245/35R21 vs 245/40R21 (−3.36%)
- 275/35R21 vs 245/40R21 (−0.48%)
- 325/30R21 vs 245/40R21 (−0.14%)
- 245/40R21 vs 285/35R21 (+0.48%)
- 245/40R21 vs 255/40R21 (+1.10%)
- 245/40R21 vs 265/40R21 (+2.19%)
- 245/40R21 vs 245/45R21 (+3.36%)
- 245/40R21 vs 275/30R22 (−0.77%)
- 245/40R21 vs 285/30R22 (+0.05%)
- 245/40R21 vs 245/35R22 (+0.12%)
- 245/40R21 vs 295/30R22 (+0.88%)
- 245/40R21 vs 255/35R22 (+1.08%)
Sizes within 3% of 28.72 in diameter
- 285/30R22 28.73 in (+0.05%)
- 215/75R16 28.70 in (−0.07%)
- 225/55R19 28.74 in (+0.10%)
- 275/45R19 28.74 in (+0.10%)
- 245/45R20 28.68 in (−0.12%)
- 315/35R20 28.68 in (−0.12%)
- 245/35R22 28.75 in (+0.12%)
- 325/30R21 28.68 in (−0.14%)
- 275/40R20 28.66 in (−0.19%)
- 245/50R19 28.65 in (−0.25%)
- 225/60R18 28.63 in (−0.30%)
- 245/55R18 28.61 in (−0.37%)
- 275/35R21 28.58 in (−0.48%)
- 285/35R21 28.85 in (+0.48%)
- 245/60R17 28.57 in (−0.49%)
- 235/75R15 28.88 in (+0.56%)
- 245/65R16 28.54 in (−0.62%)
- 225/65R17 28.52 in (−0.70%)
- 275/30R22 28.50 in (−0.77%)
- 235/70R16 28.95 in (+0.82%)
- 295/30R22 28.97 in (+0.88%)
- 285/40R20 28.98 in (+0.90%)
- 265/50R18 28.43 in (−0.99%)
- 235/65R17 29.03 in (+1.08%)
- 255/35R22 29.03 in (+1.08%)
- 225/70R16 28.40 in (−1.10%)
- 255/40R21 29.03 in (+1.10%)
- 255/45R20 29.04 in (+1.11%)
- 255/50R19 29.04 in (+1.12%)
- 255/55R18 29.04 in (+1.14%)
- 265/45R19 28.39 in (−1.14%)
- 255/60R17 29.05 in (+1.15%)
- 255/65R16 29.05 in (+1.17%)
- 255/70R15 29.06 in (+1.18%)
- 265/40R20 28.35 in (−1.29%)
- 285/45R19 29.10 in (+1.33%)
- 235/60R18 29.10 in (+1.34%)
- 235/45R20 28.33 in (−1.36%)
- 265/35R21 28.30 in (−1.44%)
- 295/35R21 29.13 in (+1.44%)
- 295/40R19 28.29 in (−1.48%)
- 225/75R15 28.29 in (−1.49%)
- 265/30R22 28.26 in (−1.59%)
- 235/55R19 29.18 in (+1.60%)
- 235/50R19 28.25 in (−1.62%)
- 305/30R21 28.20 in (−1.78%)
- 235/55R18 28.18 in (−1.88%)
- 225/75R16 29.29 in (+1.99%)
- 295/40R20 29.29 in (+2.00%)
- 295/35R20 28.13 in (−2.04%)
- 265/35R22 29.30 in (+2.04%)
- 205/75R16 28.11 in (−2.13%)
- 235/45R21 29.33 in (+2.13%)
- 235/60R17 28.10 in (−2.14%)
- 285/45R18 28.10 in (−2.15%)
- 265/40R21 29.35 in (+2.19%)
- 265/45R20 29.39 in (+2.34%)
- 255/50R18 28.04 in (−2.36%)
- 255/45R19 28.04 in (−2.37%)
- 255/40R20 28.03 in (−2.39%)
- 235/65R16 28.03 in (−2.40%)
- 255/35R21 28.03 in (−2.40%)
- 255/30R22 28.02 in (−2.41%)
- 275/25R24 29.41 in (+2.43%)
- 215/65R17 28.00 in (−2.48%)
- 265/50R19 29.43 in (+2.50%)
- 315/30R22 29.44 in (+2.52%)
- 285/40R19 27.98 in (−2.58%)
- 295/30R21 27.97 in (−2.60%)
- 245/75R15 29.47 in (+2.62%)
- 235/70R15 27.95 in (−2.66%)
- 245/70R16 29.50 in (+2.74%)
- 265/60R17 29.52 in (+2.80%)
- 245/65R17 29.54 in (+2.87%)
- 245/60R18 29.57 in (+2.99%)
- 225/50R19 27.86 in (−2.99%)
Open 245/40R21 in the tire size calculator
Source: Calculated from standard tire geometry formulas. Verified . How these numbers are calculated.