315/70R18 Tire Size in Inches and Millimeters
315/70R18 tires have a diameter of 35.4" (899 mm), a tread width of 12.4" (315 mm), and a wheel diameter of 18" (457.2 mm).The sidewall of the tire is 8.7" (221 mm), and the tire's circumference is 111.2" (2822.9 mm). This means a 315/70R18 tire will make make 570 revolutions per mile, or 354 revolutions per kilometer.
| Spec | Inches | Metric |
|---|---|---|
| Diameter | 35.4" | 899 mm |
| Width | 12.4" | 315 mm |
| Wheel | 18" | 457.2 mm |
| Sidewall | 8.7" | 221 mm |
| Circum | 111.2" | 2822.9 mm |
| Revolutions | 570 per mile | 354 per km |
What Does 315/70R18 Mean?
The tire size 315/70R18 is a common size used on many trucks, SUVs, and other larger vehicles.
Here is what each part of the size designation represents:
- 315: This number represents the width of the tire in millimeters. In this case, the tire is 315 millimeters wide.
- 70: This number represents the aspect ratio of the tire, which is the height of the tire's sidewall as a percentage of its width. In this case, the sidewall height is 70% of the tire's width.
- R: This letter indicates the tire's construction type. “R” stands for radial construction, which is the most common type of tire construction today.
- 18: This number represents the diameter of the wheel that the tire is designed to fit on, in inches. In this case, the tire is designed to fit on a 18-inch wheel.
How To Convert 315/70R18 Into Inches
The 315/70R18 conversion is fairly simple. The first number in the tire size, 315, represents the width of the tire in millimeters. To convert this to inches, we divide 315 by 25.4 (since there are 25.4 millimeters in an inch). This gives us approximately 12.4 inches.
The second number in the tire size, 70, represents the aspect ratio or the height of the tire as a percentage of its width. To calculate the height in inches, we multiply 12.4 by 0.70, which gives us approximately 8.7 inches.
Finally, the last number in the tire size, 18, represents the diameter of the wheel rim in inches. Therefore, the tire size 315/70R18 can be expressed in inches as roughly 12.4 inches wide, 8.7 inches tall, and designed to fit a 18-inch wheel rim.
Frequently Asked Questions About 315/70R18 Tires
How tall is a 315/70R18 tire?
A 315/70R18 tire has an approximate height, also known as the overall diameter, of 35.4 inches (899 mm). This height can vary slightly depending on the brand and model of the tire, as well as the amount of air pressure in the tire.How wide is a 315/70R18 tire?
A 315/70R18 tire has a width of approximately 12.4 inches (315 millimeters). The width of the tire is the first number in the tire size designation, which in this case is “315”. It’s important to note that the actual width of the tire may vary slightly depending on the brand and model of the tire, and the width may also be affected by the amount of air pressure in the tire.Alternate 315/70R18 Replacement Tire Sizes
Upsizing your wheels or tires? Replacement tires must be within 3% of the diametor of the original tire. The following sizes fall within that range - click on any size to see detailed info about that tire and wheel combination.
| Size | Diameter | Width | Wheel |
|---|---|---|---|
| 255/30R30 | 36.1" | 916 mm | 30 mm |
| 275/25R30 | 35.4" | 900 mm | 30 mm |
| 275/80R18 | 35.3" | 897 mm | 18 mm |
| 285/55R22 | 34.4" | 873 mm | 22 mm |
| 285/65R20 | 34.6" | 878 mm | 20 mm |
| 285/75R18 | 34.8" | 885 mm | 18 mm |
| 295/45R24 | 34.5" | 876 mm | 24 mm |
| 295/55R22 | 34.8" | 883 mm | 22 mm |
| 295/65R20 | 35.1" | 892 mm | 20 mm |
| 295/75R17 | 34.4" | 874 mm | 17 mm |
| 305/35R26 | 34.4" | 874 mm | 26 mm |
| 305/45R24 | 34.8" | 884 mm | 24 mm |
| 305/55R22 | 35.2" | 895 mm | 22 mm |
| 305/60R20 | 34.4" | 874 mm | 20 mm |
| 305/70R18 | 34.8" | 885 mm | 18 mm |
| 305/75R18 | 36" | 915 mm | 18 mm |
| 315/20R30 | 35" | 888 mm | 30 mm |
| 315/40R25 | 34.9" | 887 mm | 25 mm |
| 315/40R26 | 35.9" | 912 mm | 26 mm |
| 315/45R24 | 35.2" | 894 mm | 24 mm |
| 315/50R22 | 34.4" | 875 mm | 22 mm |
| 315/60R20 | 34.9" | 886 mm | 20 mm |
| 315/70R17 | 34.4" | 874 mm | 17 mm |
| 315/70R18 | 35.4" | 899 mm | 18 mm |
| 315/75R16 | 34.6" | 878 mm | 16 mm |
| 325/45R24 | 35.5" | 902 mm | 24 mm |
| 325/50R22 | 34.8" | 885 mm | 22 mm |
| 325/55R22 | 36.1" | 917 mm | 22 mm |
| 325/60R20 | 35.4" | 898 mm | 20 mm |
| 325/65R18 | 34.6" | 879 mm | 18 mm |
| 325/70R17 | 35" | 888 mm | 17 mm |
| 335/35R26 | 35.2" | 894 mm | 26 mm |
| 335/40R24 | 34.6" | 878 mm | 24 mm |
| 335/55R20 | 34.5" | 876 mm | 20 mm |
| 335/70R16 | 34.5" | 876 mm | 16 mm |
| 345/45R24 | 36.2" | 920 mm | 24 mm |
| 345/75R16 | 36.4" | 924 mm | 16 mm |
| 355/40R24 | 35.2" | 894 mm | 24 mm |
| 355/65R18 | 36.2" | 919 mm | 18 mm |
| 355/70R16 | 35.6" | 904 mm | 16 mm |
| 365/70R16 | 36.1" | 918 mm | 16 mm |
| 375/40R24 | 35.8" | 910 mm | 24 mm |
| 375/45R22 | 35.3" | 897 mm | 22 mm |
| 375/55R20 | 36.2" | 920 mm | 20 mm |
| 375/60R18 | 35.7" | 907 mm | 18 mm |
| 375/65R16 | 35.2" | 894 mm | 16 mm |
| 385/35R24 | 34.6" | 880 mm | 24 mm |