How to Read Tire Size Specifications?
2 Answers
Tire size specifications are introduced as follows: 1. Taking 195/55R15 as an example: 195 indicates the section width, which is the area of the tire that can contact the ground, measured in millimeters. 2. 55 represents the aspect ratio, which is the ratio of the tire's section height to its section width. 3. R stands for the construction code, with R being the abbreviation for radial tire. 4. 15 denotes the inner diameter of the tire, which is also the diameter of the wheel rim, usually measured in inches. Here is some additional information about tires: Tires also have speed rating letter codes, indicating the maximum speed at which the tire can carry a specified load under defined conditions. Letters from A to Z represent certified speed ratings ranging from 4.8 km/h to 300 km/h.
When I first started getting into cars, I was completely baffled by the string of numbers on tires. Later, a friend taught me how to read them: look for markings on the tire sidewall, like 205/55 R16. The 205 is the width in millimeters—the larger the number, the wider the tire. The 55 is the aspect ratio, which is the height as a percentage of the width. The R stands for radial construction, which most cars use nowadays. The 16 is the wheel diameter in inches. Understanding these helps you match the original factory size when choosing new tires, avoiding unstable driving or high fuel consumption. After my first mistake in reading the size wrong, I experienced severe vibrations, so I made it a habit to check every quarter. I recommend beginners take a photo of the original tire specs or check the vehicle manual—it’s a simple thing, don’t overcomplicate it. A lower aspect ratio improves handling, while a higher one offers more comfort, but always confirm the match before driving. This stuff affects safety, so don’t take it lightly.
