Tire size designation

Tire size designation

A tire’s sidewall is marked with a tire size designation. 

You will need this information when selecting replacement tires for your car. 

The following explains what the letters and numbers in the tire size designation mean.

Example tire size designation:

(These numbers are provided as an example only; your tire size designator could vary depending on your vehicle.)

P225/55R17 95H

P - Applicable vehicle type (tires marked with the prefix “P’’ are intended for use on 

passenger cars or light trucks; however, not all tires have this marking).

225 - Tire width in millimeters.

55 - Aspect ratio. The tire’s section height as a percentage of its width. 

R - Tire construction code (Radial).

17 - Rim diameter in inches.

95 - Load Index, a numerical code associated with the maximum load the tire can carry.

H - Speed Rating Symbol. See the speed rating chart in this section for additional information.

 

Wheel size designation

Wheels are also marked with important information that you need if you ever have to replace one. The following explains what the letters and numbers in the wheel size designation mean.

Example wheel size designation:

6.5JX17

6.5 - Rim width in inches.

J - Rim contour designation.

17 - Rim diameter in inches