What Do the Codes on Tires Mean?

[DelParker]

Tire model codes are mostly marked in formats like: 215/70R15. The meanings of these numbers are respectively: 1. Tire section width: 215 indicates the tire section width in millimeters (mm), generally ranging between 145-285mm with intervals of 10mm. 2. Aspect ratio: 70 represents the aspect ratio, which is the ratio of the tire sidewall height to the tire section width, meaning 70%. Typically, tire aspect ratios range from 30% to 80%. Under normal circumstances, ordinary sedans should not use tires with an aspect ratio >75%, while luxury cars and high-performance sports cars are recommended to use tires with an aspect ratio <60%. 3. Radial construction: R stands for Radial, indicating the tire has a radial structure. 4. Rim diameter: 15 denotes the rim diameter in inches.