Do You Know How to Read Tyre Size? Here is your Mini Guide

The tyre size comes on the sidewall with useful information about pattern, load index index, speed index and more. This article will help you to understand the details on tire's sidewall to make the right decision while purchasing tyres for your car.

For example we'll use tyre size P205/65 R15 to explain tire sidewall information.

1. TYRE SIZE

On Tyre Size the initial 'P' stands for passenger car tyres, 'T' stands for temporary spare tyres, 'LT' stands for light truck tyres. Let's know more about the structure of tire size mentioned on the sidewall.

A. TYRE WIDTH

In our example tyre size P205/65 R15, the 3 digit numeric value 205 is the section width of tire which is measured in millimeters.

B. ASPECT RATIO/PROFILE

In our example tyre size P205/65 R15, the 2 digit numeric value 65 is the aspect ratio of tire which is percentage of section width used as sidewall section height.

C. CONSTRUCTION

The letter R signifies the Radial construction which is most popular tire type mostly found.

D. RIM DIAMETER

In our example tyre size the last 2 digit numeric value 15 is the rim diameter mostly shown in inches. For heavy trucks you find the rim diameter shown in half incheswhich is radius of the tire.

2. TYRE BRAND

You'll find the tire brand mentioned on the sidewall of tire.

3. LOAD INDEX

Mostly you'll find the load index mentioned with speed rating. For example you'll see 94V in which 94 is the load index and V is the speed index for the tire.

4. SPEED INDEX

The speed index is shown in letters such as Y, W, Z or others with speed limit details provided by the manufacturers for each speed rating letter.

5. MOUNTING DIRECTION

In directional tires you'll find the mounting direction recommended by the tire manufacturers. Proper mounting of tires is very important to avoid explosion. Your car tires should by mounted by specially trained tire technicians only.

The other information available on tire's sidewall includes the maximum load and pressure, tyre construction, tyre wear indicator and tyre's pattern.