The string of numbers and letters on the side of your tyre is not random. It tells you the size, how much weight the tyre can carry, how fast it is rated to go and even when it was made. Here is how to make sense of it.
The size code
Take a common example like 205/55 R16 91V. The 205 is the tyre width in millimetres. The 55 is the aspect ratio, or how tall the sidewall is as a percentage of that width. The R means radial construction, and the 16 is the wheel diameter in inches.
Load index and speed rating
The 91 is the load index, which maps to the maximum weight the tyre can carry. The final letter, V here, is the speed rating. It is important to match or exceed the ratings your vehicle was designed for, because fitting an under-rated tyre can be unsafe and may affect your insurance.
The date your tyre was made
Look for a four digit code in an oval, such as 2225. That means the tyre was made in the 22nd week of 2025. Tyres age even when they are barely used, so the date is worth checking on a car that does low kilometres.
If the markings are hard to read or you are not sure what suits your car, we can help. Our team matches the right size and rating on every tyres and wheels job. Drivers from Kent Town and across the inner east are welcome to drop in or book a fitting.