255/45R21 Tires
255/45R21 Conversion
When converted to inches, 255/45R21 is equivalent to 30x10R21.
255/45R21 tire has a section width of 10 inches which is the measurement of tire's width from its inner sidewall to its outer sidewall. Rim diameter of 21 inches represents the size of the wheel the tire can be mounted on. Sidewall height of 4.5 inches (115 mm) is the measurement from the wheel rim to top of the tire tread. Overall diameter of 30 inches (763 mm) reflects the outer diameter of the tire and stands for tire height. Circumference of 94.2 inches (2395.8 mm) is the outer perimeter of the tire. Tire revolutions indicate the number of times a tire revolves while it covers the distance in miles or kilometers. 255/45R21 tire makes 673 revolutions per mile (417 revolutions per kilometer).



Metric | Inches | |
---|---|---|
Overall Diameter (Tire Height) | 763 mm | 30" |
Tread Width | 255 mm | 10" |
Rim Diameter | 533.4 mm | 21" |
Sidewall Height | 115 mm | 4.5" |
Circumference | 2395.8 mm | 94.2" |
Revolutions | 417 per km | 673 per mile |
Best Prices on 255/45R21 Tires | |
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255/45R21 Replacement Tire Sizes
Replacement tires have to be within 3% of the original tire's overall diameter. 255/45R21 tire can be replaced with 26 compatible tire sizes. Select optional plus size to see its specs.
Tire Size | Overall Diameter | Difference |
---|---|---|
315/25R23 | 29.2" (742 mm) | -2.8% |
305/30R22 | 29.3" (743 mm) | -2.6% |
235/45R21 | 29.3" (745 mm) | -2.4% |
265/40R21 | 29.3" (745 mm) | -2.4% |
265/35R22 | 29.3" (745 mm) | -2.4% |
305/35R21 | 29.4" (747 mm) | -2.1% |
315/30R22 | 29.5" (749 mm) | -1.8% |
275/35R22 | 29.6" (751 mm) | -1.6% |
315/35R21 | 29.6" (753 mm) | -1.3% |
275/40R21 | 29.6" (753 mm) | -1.3% |
245/45R21 | 29.6" (753 mm) | -1.3% |
285/35R22 | 29.9" (759 mm) | -0.5% |
285/40R21 | 30" (761 mm) | -0.3% |
295/30R23 | 30" (762 mm) | -0.1% |
255/40R22 | 30" (763 mm) | 0% |
295/35R22 | 30.1" (765 mm) | 0.3% |
295/40R21 | 30.3" (769 mm) | 0.8% |
265/45R21 | 30.4" (771 mm) | 1% |
265/40R22 | 30.4" (771 mm) | 1% |
305/35R22 | 30.4" (773 mm) | 1.3% |
315/35R22 | 30.7" (779 mm) | 2.1% |
275/40R22 | 30.7" (779 mm) | 2.1% |
325/30R23 | 30.7" (780 mm) | 2.2% |
275/45R21 | 30.7" (781 mm) | 2.4% |
285/35R23 | 30.9" (784 mm) | 2.8% |
315/40R21 | 30.9" (785 mm) | 2.9% |