255/30R21 Tires

255/30R21 Conversion

When converted to inches, 255/30R21 is equivalent to 27x10R21.

255/30R21 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 3 inches (77 mm) is the measurement from the wheel rim to top of the tire tread. Overall diameter of 27 inches (687 mm) reflects the outer diameter of the tire and stands for tire height. Circumference of 84.8 inches (2157.2 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. 255/30R21 tire makes 747 revolutions per mile (464 revolutions per kilometer).

255/30R21 Section Width
10"
27"
255/30R21 Tire Side
Tire Circumference
84.8"
21"
3"
747 Revs/Mile
Metric Inches
Overall Diameter (Tire Height) 687 mm 27"
Tread Width 255 mm 10"
Rim Diameter 533.4 mm 21"
Sidewall Height 77 mm 3"
Circumference 2157.2 mm 84.8"
Revolutions 464 per km 747 per mile

255/30R21 Replacement Tire Sizes

Replacement tires have to be within 3% of the original tire's overall diameter. 255/30R21 tire can be replaced with 19 compatible tire sizes. Select optional plus size to see its specs.

Tire Size Overall Diameter Difference
275/25R21 26.4" (671 mm) -2.3%
235/30R21 26.6" (675 mm) -1.7%
295/25R21 26.8" (681 mm) -0.9%
245/30R21 26.8" (681 mm) -0.9%
375/20R21 26.9" (683 mm) -0.6%
305/25R21 27" (685 mm) -0.3%
265/25R22 27.2" (691 mm) 0.6%
265/30R21 27.3" (693 mm) 0.9%
225/30R22 27.4" (695 mm) 1.2%
325/25R21 27.4" (695 mm) 1.2%
235/35R21 27.4" (697 mm) 1.5%
275/25R22 27.4" (697 mm) 1.5%
275/30R21 27.5" (699 mm) 1.7%
235/30R22 27.6" (701 mm) 2%
285/25R22 27.6" (701 mm) 2%
285/30R21 27.8" (705 mm) 2.6%
245/35R21 27.8" (705 mm) 2.6%
295/25R22 27.8" (707 mm) 2.9%
245/30R22 27.8" (707 mm) 2.9%