Knowing how to read the size on your tyre is important when requesting a repair or replacement. The numbers and letters printed on the tyre sidewall give key information about its dimensions and capabilities. Here’s a breakdown of what each part means, as shown in the image below:

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• Width (225) – This is the width of the tyre in millimetres, measured from sidewall to sidewall.

• Profile (45) – Also known as the aspect ratio, this number shows the height of the sidewall as a percentage of the tyre’s width. In this case, 45% of 225mm.

• Tyre Construction (R) – This indicates the internal structure of the tyre. "R" stands for radial construction, which is the most common type.

• Rim Size (18) – This is the diameter of the wheel (rim) in inches that the tyre fits onto.

• Load Index (91) – This number represents the maximum weight the tyre can safely carry. You can refer to a load index chart to find the exact weight.

• Speed Rating (Y) – This letter shows the maximum speed the tyre can handle when properly inflated. Each letter corresponds to a speed rating (e.g., Y = up to 186 mph or 300 km/h).

If you’re unsure what tyre size you need for a puncture repair or replacement, just send us a photo of this section or read the markings over the phone when you call 0330 341 3416.