The first letter on a tire indicates the tire’s class. P designates this tire as a passenger car tire, an LT before the tire size would mean the tire is a light truck tire, and a European metric tire would have no letter before the tire size.
Tire Width is the width of the tire measured in millimeters from sidewall to sidewall. The first three-digit number in the tire size refers to the tire width. For instance, in a size P215/65 R15 tire, the width is 215 millimeters. Aspect Ratio is the ratio of the height of the tire's cross-section to its width. The two-digit number after the slash mark in a tire size is the aspect ratio.
What do the numbers on tires mean? There's a massive amount of information branded on the sidewall of every tire ... but it's written in code. The tire size is just one small piece of this code. The tire size "P225/45R17 91V" may not mean much to the average person, but to tire geeks like us it speaks volumes.
What do the numbers mean on the sidewall of your tire? At first glance, you look at your tire sidewall and think, “’Do I need a super secret decoder ring to read this?” In addition to the model name of the tire there is a series of numbers that at first, you don’t deem important.
There’s a lot to learn from the soup of letters and numbers on the sidewall of a tire, but deciphering all of that data takes some explanation. Knowing what the information means, a consumer can decide if a tire is right for their vehicle, driving style, and road conditions.
"The tire size branded on the sidewall provides a significant amount of information about the tire's intended purpose, dimensions, load capacity and high temperature/high speed durability." Service Type. Most tire sizes begin with a letter or letters that identify the type of vehicle and/or type of service for which they were designed.
The two-digit number after the slash mark in a tire size is the aspect ratio. For example, in a size P215/65 R15 tire, the 65 means that the height is equal to 65% of the tire's width. The bigger the aspect ratio, the bigger the tire's sidewall will be.
The 235 is the width of the tire in millimeters (mm), measured from sidewall to sidewall. Since this measure is affected by the width of the rim, the measurement is for the tire when it is on its intended rim size. This number tells you the height of the tire, from the bead to the top of the tread ...
The first number in this series refers to the tire's section width, or the distance from sidewall edge to sidewall edge, measured in millimeters up and over the tire's tread.
Automobile tires are described by an alphanumeric tire code (in American English and Canadian English) or tyre code (in British English, Australian English and others), which is generally molded (or moulded) into the sidewall of the tire. This code specifies the dimensions of the tire, and some of its key limitations, such as load-bearing ...