Look at the sides of your tyres. You'll find a code of letters and numbers.
e.g. 205/55R16 88V
Each letter and number conveys important information, like whether a particular tyre will be compatible with your vehicle.
Some tyre designations are prefixed with a letter
Light truck tyre
The first number is a three-digit number which refers to the overall width of the tyre in millimetres.
The second number refers to the aspect ratio, which is the relationship between the tyre's height and its width. In this example, the sidewall's height is about 55% of the tyre's width.
The letter following the aspect ratio is usually an 'R' which stands for radial.
The next number indicates the diameter of the wheel rim (in inches) on which the tyre will fit.
The load index is an assigned number that corresponds with the load-carrying capacity of the tyre.
The speed rating is a letter which indicates the range of speeds at which a tyre is certified to carry a load. Each tyre is assigned a rating from A (lowest) to Z (highest).
Markings do not always appear exactly as they do in this example, as tyres can be certified under a variety of designations.