Most people get confused when they see all the numbers and alphabets on a tyre, not realizing that they are important and fairly simple to decode. We have got this guide for you to understand tyres easily.
Most consumers will never pay much attention to what wheels, tyres, or tyre-size their cars have even though the tyre is the most relevant component of a car. It is the only thing that makes a vehicle move, you can have the best engine but it’ll be of no use if the tyres aren’t up to scratch. But as important as they are, people tend to spend the least amount of time when choosing new tyres for their cars. We at IndianAuto have come up with a guide to help you how to choose tyre for your car that extract the best performance out of your vehicle.
You may not realize this but tyres end up affecting almost all aspects of any car. The braking, acceleration, handling, ride quality, suspension, and even fuel consumption get influenced by your tyres. So it is only a fair deal to learn the basics to keep in mind when changing for new tyres.
What do the numbers and alphabets on your tyre mean?
As you can see in the image above, the numbers in the tyre might confuse you a little initially, not to worry as we’ll help you here. After finishing this guide, you’ll understand how simple it to decode.
Here, 205 denotes the width of the tyre in mm, it is the amount of area the tyre will remain in contact with the ground. The wider the width, the higher the amount of grip from the tyre. Around a corner, the handling and stability of a car will depend solely on how much grip you have on the road, which is a result of how much area of the tyre is in contact with the road.
Next, 55 denotes the height of the sidewall of the tyre, in the percentage of the width. In this case, 55% of 205 means 113 mm. The higher the sidewall of a tyre, the more rubber it has and resultantly, the better the bump-absorption characteristics. Therefore, the height of the sidewall relates directly to the ride quality of a car.
R represents Radial, which means that the metallic wires inside the tyres are at 90 degrees to the face of the tyre. Usually, all passenger cars nowadays come with radial tyres.
16 indicates the size of the wheel in inches.
91 is the load index of a tyre, and it is very important as it represents the maximum weight a tyre can carry and operate safely and smoothly. The load index starts from 20 and goes up all the way to 99. As a reference, the table below demonstrates some of the common load indices used in a number of vehicles.
Similar to the load index, every tyre is designed for a maximum speed at which it can operate safely and smoothly. This is called the speed index, and it is represented by the V in a tyre. The table below shows the speed indices used by various cars.
Max Speed (km/h)
Max Speed (km/h)
High and Low Profile Tyres
Tyres can also be classified as High and low profile tyres and therefore find use in various scenarios and cars.
High-performance car use low-profile tyres which mean that the tyre will be very wide but the sidewalls won’t be as high. For example, a Mercedes E-63 AMG S comes shod with 295/30 R20 rear tyres. It needs such a wide tyre as it is important the car grips the road well enough to withstand very fast acceleration and high cornering speeds. If you end up buying narrower tyres, the performance of the car will be hampered significantly.
SUVs are the opposite of performance cars, i.e., it goes to places where sometimes roads cease to exist. The first requirement here is ride quality to ensure comfort for the occupants, which is why high profile tyres are used. The Mahindra Thar uses 245/75 R16 tyres, which means the sidewall of this tyre will be very high so it can absorb all the bumps and undulations of the road.
Normal cars that are used for day-to-day use generally try to strike a balance between the two extremes of high and low profile tyres. These tyres make sure they can provide good ride quality and safe handling characteristics for everyday use.
We hope this guide will help you on how to choose tyre for car depending on your requirements.