Tire numbers can be confusing, especially if you’re not familiar with them. However, they hold valuable information about your vehicle’s performance and safety on the road. The numbers and letters embossed on your tire’s sidewall can tell you a lot about the tire’s size, weight capacity, speed rating, and more.

To learn more about the numbers on tires, let’s go through an example tire number and break down what each digit means. Understanding the tire number meaning will help you make informed decisions when selecting the right tire for your vehicle.
How to Read Tire Numbers
Let’s take the example tire number of P205/55R16 91s to understand what each segment of the code indicates.
- P denotes a “P-Metric Tire,” which is the type of tire typically found on passenger vehicles. The first number.
- 205 indicates the tire width in millimeters, from sidewall to sidewall.
- 55 refers to the aspect ratio or the ratio of the tire’s height to its width. In this case, the tire has a height that’s equal to 55% of its width.
- R represents radial construction, which is the most common tire construction.
- 16 refers to the wheel size, and this tire fits on a 16-inch wheel.
- 91 represents the load index and speed rating. The load index, which is the number “91,” indicates the maximum weight that the tire can handle when properly inflated.
- S represents the speed rating, which ranges from A to Z ratings. “S” indicates that this tire can handle a maximum speed of 112 mph.
Knowing how to decipher tire numbers is crucial in choosing the right tire for your vehicle and its intended use. Once you have the right set of tires, it’s important to maintain them properly.
Ongoing tire maintenance, including regular inspections and proper inflation, can help extend tire life, improve fuel efficiency and ensure safer handling on the road.
Importance of Tire Size
Now that you understand tire size and what the numbers and letters on your tire represent, you may be wondering why it’s so important to know these details.
Here’s why tire size matters when it comes to driving efficiently and safely:
- Tire size influences your vehicle’s grip on the road, with larger tires generally providing more traction on the road.
- Wider tires cover more ground and offer added stability and support to your vehicle.
- If you enjoy off-road driving or plan on driving in rough terrain, you’ll want to consider larger tires to ensure your vehicle is well-equipped for such conditions.
- On the other hand, smaller wheels can provide better handling and maneuverability when driving through city traffic.
- Each part of a tire contributes to its overall performance and safety, making proper tire care and maintenance essential.