What do the letters and numbers on tires represent?

[CarsonLynn]

The meanings of the numbers and letters on tires are as follows: Take a tire marked with 225/60-R17-99H as an example: 1. 225 represents the section width, which can be simply understood as the width of the tire tread; 2. 60 represents the aspect ratio, which can be simply understood as the height of the tire sidewall; 3. R represents the tire type code, where R stands for radial tire; 4. 17 represents the rim diameter, meaning the tire is suitable for 17-inch rims; 5. 99 represents the load index of the tire, indicating the maximum weight the tire can bear, with 99 corresponding to a maximum weight of 775KG; 6. H represents the speed rating of the tire, indicating the maximum speed the tire can handle, with H corresponding to a maximum speed of 210KM/H.

[DiKing]

When you see the letters and numbers on a tire, such as 205/55R16 91V, they are like the tire's ID card, recording key information. 205 represents the tire width in millimeters—the larger the number, the stronger the grip but slightly higher fuel consumption. 55 is the aspect ratio percentage, indicating the sidewall height relative to the width—a smaller number means better handling but less comfort. R stands for radial construction, which is durable, and 16 is the rim size in inches. 91 is the load index—the higher the number, the greater the weight it can bear. V is the speed rating, allowing a maximum speed of 240 km/h. When buying new tires, all these must match your vehicle model; otherwise, handling and safety issues may arise. Regularly check the DOT code to see the production date and avoid aging tires.

[Kendall]

Tire markings are the fundamental guarantee for safe driving. First, the first two digits indicate the width, the middle number represents the aspect ratio affecting cushioning performance; letters like R denote the radial construction, and the following number must match the correct rim diameter. Subsequent indices such as 95 indicate the maximum load capacity, while an H rating permits high-speed driving. Incorrect values can lead to longer braking distances and increased risk of unstable steering. The production date is found in the last four digits of the DOT code, e.g., 2324 means the 23rd week of 2024. Regular inspections ensure no excessive wear, forming a habit to prevent blowout accidents.

[VivianRose]

In the eyes of car enthusiasts, tire codes are the soul of tuning. Wide tires like 265 enhance grip but require high-speed ratings to match modified power; low aspect ratios like 40 optimize handling response at the cost of slightly reduced shock absorption. The R structure is standard and reliable, while letters like W at the end ensure peak performance doesn't degrade. The load index relates to stability when carrying modified loads—don't overlook the DOT code to choose fresh tires, as aging can weaken performance.