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).

255/45R21 Section Width
10"
30"
255/45R21 Tire Side
Tire Circumference
94.2"
21"
4.5"
673 Revs/Mile
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

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%