How to Identify Your Car’s Tire Size

Introduction

Understanding your car’s tire size is essential for maintaining optimal performance, safety, and comfort. Whether you’re replacing old tires or just checking for compatibility, knowing how to read tire size can save you time and money. In this guide, we'll walk you through the process of identifying your vehicle’s tire size with ease.

1. Find the Tire Size on Your Car

The easiest way to determine your car’s tire size is to look at the sidewall of your current tires.

Wheel Close-Up

2. Understand the Tire Size Code

Tire size codes follow a specific format. Here’s how to break it down:

• Example Code: (P)225/40ZR18 92Y

• P: Type of tire (P stands for passenger, but it could be omitted from the sidewall).

• 225: Tire width in millimeters from sidewall to sidewall.

• 40: Aspect ratio (the height of the sidewall as a percentage of the width).

• ZR: Tire construction type (R stands for radial, which is the most common type).

• 18: Diameter of the wheel in inches that the tire fits.

• 94Y: Load index and speed rating (92 is the load index, and Y is the speed rating).

Tire Close-Up

3. Understand the Tire Speed Rating

Speed ratings are found in the tire size code of the tire. Here are the most common ratings:

• T: 118 mph (190 km/h)

• H: 130 mph (210 km/h)

• V: 149 mph (240 km/h)

• Z*: Over 149 mph (240 km/h; often used in combination with other letters, such as W or Y, for tires rated above 149 mph)

• W: 168 mph (270 km/h)

• Y: 186 mph (300 km/h)

Speed Rating Reference Sheet

Get to Work

The final step is to get out there apply what you learned! Make sure to get a set of tires that best suit your build and keep you safe on the road or track. Remember, it's better off built!