What does 305/75R18 mean?
305/75R18 is a tire size with the following dimensions:
- 305 is the width of the tire in millimeters. This number also indicates the appropriate width of the rim on which the tire should be mounted.
- 75 is the aspect ratio, which is the ratio of the tire's height to its width. This affects the tire's handling and ride comfort
- R indicates the tire's construction type, meaning it has a radial construction. This provides stability and precision to the tire.
- 18 is the diameter of the wheel in inches, on which the tire is to be mounted.
305/75R18 Tire Conversion
| Dimensions | Inches | Millimeters |
| Tire Diameter | 36 in | 914.7 mm |
| Section Width | 12 in | 305 mm |
| Rim Height | 18 in | 457 mm |
| Sidewall Height | 9 in | 228.8 mm |
| Circumference | 113.1 in | 2873.6 mm |
| Revolutions | 560 revs/mile | |
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FAQ About 305/75R18 Tire
How tall is a 305/75R18 tire?
The height (or diameter) of a 305/75R18 tire is 36 inches
How wide is a 305/75R18 tire?
The width of a 305/75R18 tire is 305 mm, which is about 12 inches.
What size rim fits a 305/75R18 tire?
A 305/75R18 tire fits on a rim that is 18 inches in diameter.
What does the 75 in a 305/75R18 tire mean?
The 75 in a 305/75R18 tire refers to the aspect ratio, meaning the height of the tire's sidewall is 75% of its width.
Alternative Tire Sizes for 305/75R18
Typically, it's recommended to choose a tire with a diameter (height) within 3% of the original equipment manufacturer (OEM) tire size.
However, keep in mind that this is a general guideline and not an absolute rule.
Here are some tire sizes that are compatible with the 305/75R18:
| Tire Size | Diameter | Rim |
|---|---|---|
| 275/80R18 | 35.3″ (-1.9%) | 18 x n/a |
| 315/70R18 | 35.4″ (-1.7%) | 18 x 8.0-11.0 |
| 355/65R18 | 36.2″ (0.6%) | 18 x 10.0-11.0 |
| 375/60R18 | 35.7″ (-0.8%) | 18 x n/a |