Tyre Size Explained: Types of Tyres and Sizes

Tyre size plays a vital role in determining the safety and performance of a vehicle. The right tyre ensures proper traction, optimal acceleration and fuel efficiency while improving your overall comfort. 

So, understanding what tyre size is, the importance of a tyre size, its different types and its meaning need utmost consideration while you are making any decision for your vehicle.

Tyre size refers to the dimensions and measurements of the tyre of a car. Each tyre displays several parameters in the form of numbers or alphabets such as tyre width, height, etc., to suit the area where a vehicle is driven. 

In other words, each vehicle requires a compatible tyre that fits adequately ensuring safety, comfort and hassle-free performance.

Depending on the climate and usage, there are several types of tyres available. Before we dive into the detailed explanation of tyre size, its readings and calculators, we must talk about different types of tyres. 

Here are some of the tyres that cater to different used and climatic conditions.

Winter Tyres

Winter tyres are made of high concentrations of special rubber compounds that facilitate smooth movement in extreme temperatures below 7 degrees Celsius. Besides, they consist of studs that ensure stable movement on slippery snow-clogged roads. Moreover, they contain precise grooves that help to push the snow while allowing smooth vehicle movement.

Summer Tyres

Summer tyres consist of a soft material that enhances vehicle movement in warm, humid and dry climates. These tyres are ideal for high-speed driving since the soft material improves gripping and handling. Furthermore, these tyres have a unique tread pattern that assures seamless movement on dry roads.

All Season Tyres

All-season tyres, as the name suggests, are apt for both hot and cold climates. They comprise special compounds and unique tread patterns that sustain both ends of the climatic spectrum. However, their efficiency cannot match up to the standards of a summer and winter tyre in respective seasons. One of the additional benefits is that you do not have to change them every six months.

Temporary Tyres

Space saver tyres or temporary tyres come to your rescue when your original tyre malfunctions or suffers a sudden puncture. These tyres are not appropriate for regular use and have a narrow capacity. You cannot carry heavy loads with these tyres. However, they allow you to safely reach the nearest mechanic for a new tyre installation.

Touring Tyres

Touring tyres are apt for adventure lovers who frequently embark upon interesting long drives. These tyres are specially made with a wide tread to handle long distances. While the treads ensure better stability and balance, certain additional features offer a noiseless and calm journey. Besides, these tyres are apt for wet roads giving you a matchless driving experience.

Sports Tyres

Sports tyres are commonly found in vehicles with large rim sizes. They offer a seamless driving experience with high-speed stability. The wide tread designs and soft rubber compounds ensure excellent grip on the roads. However, they are unsuitable for roads with dents and bumps since they do not have an appropriate shoulder height.

All-Terrain Tyres

All-terrain tyres are designed to withstand all types of terrains. They comprise a firm tread pattern with sturdy shoulders that ensures hassle-free movement even in hilly mountainous terrains. While they are extremely durable having a long lifespan, they come with a few drawbacks. All-terrain tyres are expensive and not fuel-efficient like regular tyres.

Mud Tyres

Mud tyres or off-roading tyres are ideal for people who embark on adventurous journeys on extremely challenging terrains. These tyres dig deep into the ground while throwing away mud and gravel to the sides. However, they are unsuitable for journeys on smooth roads and wear out in no time. Besides, they can produce annoying noise and make you uncomfortable with vibrations.

While reading a tyre size seems daunting and elaborate, it is simple if you know what the letters and numbers in the sidewalls of the tyre indicate. 

Here is a vivid explanation of the types of tyres and sizes and how to read it:

Note: (Every tyre size is usually expressed in a format that reads like- 195/55 16R 87V.)

Section Width

195 signifies the 'section width' of the tyre in mm (millimetres). The number is a measurement of the sidewalls or the distance from one side of a tire to the other side. It allows you to understand how a tyre will fit into a vehicle.

Aspect Ratio

5 is the aspect ratio of your tyre. It is a percentage of the height of a sidewall to the width of the tyre. So, here it means, the height of the sidewall is 55% of the width of your tyre. An aspect ratio determines the overall stability and performance of a tyre.

Construction Type

R signifies the radial construction of the tyre. This is the most popular type of tyre where the sidewalls comprise a layer of steel cords that lie perpendicular to the tyre's centreline. Radial tyres are known for offering exceptional comfort during rides.

Rim Diameter

16 indicates the rim diameter of a vehicle. It is the diameter of the metal rim of a tyre and is measured in inches. Simply put, it is the length of the distance between one bead seat to another. So, in the above example, the rim diameter of the tyre is 16 inches.

Load Index

87 refers to the load index and tells you how much weight your car's tyres are capable of withstanding. You can convert a load index to the original weight using a load index chart. Each number in the chart/table corresponds to a weight. For instance, in the above example, the maximum safe capacity of this tyre is 690kg or 1521 pounds.

Speed Rating

V indicates the maximum speed your tyres can withstand without wear and tear. Each alphabet corresponds to a particular speed. Similar to the load index, speed rating can be found in charts. In the above example, the maximum speed this tyre can safely withstand is 240 kilometres per hour which roughly corresponds to 149 miles per hour.

Calculating different parameters of a tyre can be daunting and overwhelming for some people. To curb this issue, there are several online tyre size calculators available that allow you to conveniently measure the different dimensions of a tyre. You have to enter the tire code (for example, 195/55 16R) to get the following dimensions.

• Tyre height or diameter

• Wheel size

• Sidewall height 

• Tyre circumference 

• Revolutions per mile

• Revolutions per kilometre

There are circumstances where you might have to change your tyres and replace them with new ones. A tyre size calculator provides you with a list of alternate tyres compatible with your older and worn-out tyres.

Tyres often wear out and necessitate the installation of new ones. However, you must carefully evaluate a few points while buying tyres.

Age of a Tyre

Tyres consist of rubber compounds that are susceptible to damage with time. So, you must purchase a tyre with a recent manufacturing date.

Size

Ensure that the tyre size ideally fits and matches the size of your vehicle. You may take the help of a user manual or online tyre size calculator to find an ideal tyre.

Weather Conditions

The weather in your area is one of the primary determining factors to consider while buying a tyre. Depending on the climatic conditions, you have to pick winter, summer or all-season tyres.

Tread Pattern

You must carefully conduct thorough research and pick a tyre with suitable tread patterns that match your needs, driving habits and weather conditions.

Warranty

Tyres that come with warranty periods must be your top priority. It is common for a tyre to undergo accidental damage, and certain manufacturers offer repair services at no additional costs.

Brand

Your safety and comfort depend majorly on the quality of the tyre you are using. Reliable brands that provide premium quality products must be your utmost priority.

This is all you want to know on what is tyre size, types, tyre size calculation and more. The explanation will provide an in-depth insight into the various aspects of tyres and their importance. 

As a result, you will be able to make wise decisions while purchasing new tyres for your vehicle. Overall, this guide will help you understand the complexities of tyres while allowing you to have a safe and comfortable driving experience.