225/75R18 in Inches

A 225/75R18 tire has a 31.3-inch diameter, a 8.9-inch width, and is designed for a 18-inch rim.

In high flotation terms, this tire is labeled as 31.3x8.9R18.

225/75R18 Tire Size
225/75R18 Tire Size in Inches
225/75R18 Tire Circumference
644.6 revs/mile

225/75R18 Tire Overview

31.3 inches
Wheel Diameter
18 inches
Tire Width
8.9 inches
98.3 inches
Sidewall Height
6.6 inches
644.6 per mile

What does 225/75R18 mean?

225/75R18 tire size meaning in inches

225/75R18 is a tire size with the following dimensions:

  • 225 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.

225/75R18 Tire Conversion

Tire Diameter31.3 in794.7 mm
Section Width8.9 in225 mm
Rim Height18 in457 mm
Sidewall Height6.6 in168.8 mm
Circumference98.3 in2496.6 mm
Revolutions644.6 revs/mile
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FAQ About 225/75R18 Tire

How tall is a 225/75R18 tire?

The height (or diameter) of a 225/75R18 tire is 31.3 inches

How wide is a 225/75R18 tire?

The width of a 225/75R18 tire is 225 mm, which is about 8.9 inches.

What size rim fits a 225/75R18 tire?

A 225/75R18 tire fits on a rim that is 18 inches in diameter.

What does the 75 in a 225/75R18 tire mean?

The 75 in a 225/75R18 tire refers to the aspect ratio, meaning the height of the tire's sidewall is 75% of its width.

Alternative Tire Sizes for 225/75R18

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 225/75R18:

Tire SizeDiameterRim
175/90R1830.4″ (-2.9%)18 x n/a
235/70R1831.0″ (-1.0%)18 x 6.5-8.5
235/75R1831.9″ (1.9%)18 x n/a
245/65R1830.5″ (-2.6%)18 x 7.0-8.5
245/70R1831.5″ (0.6%)18 x n/a
255/65R1831.1″ (-0.6%)18 x 7.0-9.0
255/70R1832.1″ (2.6%)18 x 6.5-8.5
265/60R1830.5″ (-2.6%)18 x 7.5-9.5
265/65R1831.6″ (1.0%)18 x 7.5-9.5
275/60R1831.0″ (-1.0%)18 x 7.5-9.5
275/65R1832.1″ (2.6%)18 x 7.5-9.5
285/60R1831.5″ (0.6%)18 x 8.0-10.0