Tyre Speed Rating Guide

What is a tyre speed rating and why is it important?

When it comes to tyres, it’s essential that you understand the tyre speed rating. What does it mean exactly? The speed rating that a tyre is allocated is the maximum speed that a tyre can be safely driven at. Tyre speed ratings are set by the tyre manufacturers and are based on in house testing where engineers are required to run the tyre at 6.2mph sets in 10-minute increments until the desired speed has been met.

It is fairly simple to check your speed rating of the tyre, this can be done by just looking at the sidewall of the tyre. You will find the speed rating by looking at the end of the tyre size, it will always be represented by a letter and as the example shows the tyre speed rating “H”. This would mean that your tyres could operate up to 130mph safely.

Tyre Sizes Diagram

Speed rating can range from N (87 mph) to Y (186 mph). For high-performance cars such as Ferraris and Porches they have specifically manufactured tyres made for the car. The higher speeds the wheels turn the more heat that is generated, this makes it important that your chosen tyre can cope with the extra heat. A one letter difference in speed rating can mean up to 10km/h difference in speed.

Tyre Speed Rating Table

A tyre’s speed rating is the maximum speed that the tyre is approved for by law. It ensures that the tyre you buy is correct for the speed of the car it’s fitted on. You can increase the speed rating of your car’s tyres for improved performance, but if you decrease it then you must NOT drive any faster than the tyres speed rating.