What does 31x10.50R15 mean?

Tire sizes are easy to understand once you learn how to read them.  On this page you'll find a color-coded explanation of the 31x10.50R15 tire code.

10.50

This number indicates that your tire has a width of 10.50 inches.

31

This mark reveals that your tire has a diameter of 31 inches.

15

The tire size was designed to fit rims or wheels that are 15 inches in diameter.

R

This letter denotes how your tire was constructed.  Radial is the standard construction method for about 99% of all tires sold today.

RRadial
BBias Belt
DDiagonal