275/65R18 In Inches – Tire Size & Wheel Fitment Guide

What size tire is 275/65R18 in Inches?

The 275/65R18 tire has an overall diameter of 32.1 inches, a section width of 10.8 inches, and can be mounted on 18 x 7.5-9.5 inches rim. The equivalent tire size in the high flotation system is 32.1x10.8R18.

	Inches	Millimeters
Tire Diameter	32.1	814.7
Section Width	10.8	275
Rim Height	18	457
Sidewall Height	7	178.8
Circumference	100.8	2559.5

10.8"

32.1"

100.8"

18"

7"

628.8 Revs/Mile

To help you understand, we'll break down each part of the 275/65R18 tire size to know what these numbers represent & how they may affect your tire's performance:

How wide is a 275/65R18 tire?

The 275/65R18 tire has a width of 10.8 inches (275 mm). This is the measurement at its thickest point, the distance between the outer sidewall and the inner sidewall’s widest point, also called as tread width or section width.

How tall is a 275/65R18 tire?

The 275/65R18 tire has a height of 32.1 inches (814.7 mm). This is the measurement from the bottom to the highest point at the top of a tire through its exact center when inflated and unloaded.

275/65R18 sidewall height

The 275/65R18 has a sidewall height of 7 inches (178.8 mm). It’s measured from the rim to the outer edge of the tire's tread, expressed as a percentage of tire width.

What size rim do you need for 275/65R18 tire?

You can mount the 275/65R18 tire on a rim with a height of 18 inches and a width ranging from 7.5-9.5 inches. (Based on recommendations of The Tire and Rim Association (TRA))

Putting very narrow tires on wide rims or vice versa can result in reduced performance of the tire.

275/65R18 circumference

The 275/65R18 tire has a circumference of 100.8 inches (2559.5 mm), This is the measurement of the distance the tire travels in one revolution.

The tire circumference is important for your vehicle's overall performance, affecting its speedometer acceleration, accuracy and fuel efficiency.

275/65R18 Revolutions

The 275/65R18 performs 628.8 revs/mile. Revolutions per mile indicate the number of times a tire rotates while it covers the distance of one mile.

Replacement Tire Sizes for 275/65R18

As a rule, you can replace the tire within a 3% difference in tire diameter (height) of the OEM tire size. Here is a list of compatible tire sizes for 275/65R18: