305/40R18 Tires

305/40R18 Conversion

When converted to inches, 305/40R18 is equivalent to 27.6x12R18.

305/40R18 tire has a section width of 12 inches which is the measurement of tire's width from its inner sidewall to its outer sidewall. Rim diameter of 18 inches represents the size of the wheel the tire can be mounted on. Sidewall height of 4.8 inches (122 mm) is the measurement from the wheel rim to top of the tire tread. Overall diameter of 27.6 inches (701 mm) reflects the outer diameter of the tire and stands for tire height. Circumference of 86.7 inches (2201.1 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. 305/40R18 tire makes 731 revolutions per mile (454 revolutions per kilometer).

305/40R18 Section Width
12"
27.6"
305/40R18 Tire Side
Tire Circumference
86.7"
18"
4.8"
731 Revs/Mile
Metric Inches
Overall Diameter (Tire Height) 701 mm 27.6"
Tread Width 305 mm 12"
Rim Diameter 457.2 mm 18"
Sidewall Height 122 mm 4.8"
Circumference 2201.1 mm 86.7"
Revolutions 454 per km 731 per mile

305/40R18 Replacement Tire Sizes

Replacement tires have to be within 3% of the original tire's overall diameter. 305/40R18 tire can be replaced with 74 compatible tire sizes. Select optional plus size to see its specs.

Tire Size Overall Diameter Difference
245/35R20 26.8" (680 mm) -3%
285/30R20 26.8" (680 mm) -3%
345/25R20 26.8" (680 mm) -3%
145/60R20 26.9" (682 mm) -2.7%
225/50R18 26.9" (683 mm) -2.6%
285/35R19 26.9" (683 mm) -2.6%
205/55R18 26.9" (683 mm) -2.6%
225/45R19 27" (685 mm) -2.3%
285/40R18 27" (685 mm) -2.3%
335/30R19 27" (685 mm) -2.3%
325/35R18 27" (685 mm) -2.3%
255/35R20 27" (686 mm) -2.1%
295/30R20 27" (686 mm) -2.1%
255/40R19 27" (687 mm) -2%
255/45R18 27" (687 mm) -2%
225/40R20 27.1" (688 mm) -1.9%
145/80R18 27.1" (689 mm) -1.7%
165/70R18 27.1" (689 mm) -1.7%
295/35R19 27.1" (689 mm) -1.7%
345/30R19 27.2" (691 mm) -1.4%
305/30R20 27.2" (692 mm) -1.3%
215/55R18 27.3" (693 mm) -1.1%
295/40R18 27.3" (693 mm) -1.1%
235/50R18 27.3" (693 mm) -1.1%
175/60R19 27.3" (693 mm) -1.1%
155/60R20 27.3" (694 mm) -1%
265/35R20 27.3" (694 mm) -1%
265/45R18 27.4" (695 mm) -0.9%
265/40R19 27.4" (695 mm) -0.9%
235/45R19 27.4" (695 mm) -0.9%
145/65R20 27.4" (696 mm) -0.7%
235/40R20 27.4" (696 mm) -0.7%
355/30R19 27.4" (697 mm) -0.6%
305/35R19 27.4" (697 mm) -0.6%
315/30R20 27.5" (698 mm) -0.4%
345/35R18 27.5" (699 mm) -0.3%
275/35R20 27.6" (700 mm) -0.1%
175/55R20 27.6" (700 mm) -0.1%
155/70R19 27.6" (701 mm) 0%
215/45R20 27.6" (702 mm) 0.1%
205/60R18 27.7" (703 mm) 0.3%
315/35R19 27.7" (703 mm) 0.3%
275/40R19 27.7" (703 mm) 0.3%
145/85R18 27.7" (703 mm) 0.3%
245/50R18 27.7" (703 mm) 0.3%
245/45R19 27.7" (703 mm) 0.3%
195/50R20 27.7" (704 mm) 0.4%
245/40R20 27.7" (704 mm) 0.4%
325/30R20 27.7" (704 mm) 0.4%
275/45R18 27.8" (705 mm) 0.6%
155/80R18 27.8" (705 mm) 0.6%
225/55R18 27.8" (705 mm) 0.6%
165/60R20 27.8" (706 mm) 0.7%
285/35R20 27.9" (708 mm) 1%
315/40R18 27.9" (709 mm) 1.1%
335/30R20 28" (710 mm) 1.3%
155/65R20 28" (710 mm) 1.3%
225/45R20 28" (710 mm) 1.3%
285/40R19 28" (711 mm) 1.4%
255/40R20 28" (712 mm) 1.6%
255/50R18 28.1" (713 mm) 1.7%
255/45R19 28.1" (713 mm) 1.7%
285/45R18 28.1" (713 mm) 1.7%
295/35R20 28.1" (714 mm) 1.9%
145/80R19 28.1" (715 mm) 2%
235/55R18 28.1" (715 mm) 2%
345/30R20 28.2" (716 mm) 2.1%
295/40R19 28.3" (719 mm) 2.6%
235/50R19 28.3" (719 mm) 2.6%
265/40R20 28.3" (720 mm) 2.7%
235/45R20 28.3" (720 mm) 2.7%
155/85R18 28.4" (721 mm) 2.9%
265/45R19 28.4" (721 mm) 2.9%
305/35R20 28.4" (722 mm) 3%