Not sure what the numbers on your tyre mean? This quick guide helps you find and understand your tyre size easily, so you can choose the right tyres for your vehicle without confusion.
It's actually easy to understand once you break it down. Each number and letter tells you something important about your tyre, from its width to how it performs on the road.
What Each Part Means
Width
The first number (e.g., 225) shows how wide your tyre is in millimetres.
Aspect Ratio (Profile)
The second number (e.g., 55) shows the height of the tyre sidewall as a percentage of its width.
Tyre Construction
The letter (usually R) means radial construction the most common type used in modern vehicles.
Rim Size
The number (e.g., 17) tells you the size of the wheel the tyre fits (in inches).
Load Index & Speed Rating
The final numbers and letter (e.g., 94W) indicate how much weight the tyre can carry and the maximum speed it can safely handle.
Understanding tyre size doesn’t have to be complicated. Here’s a simple breakdown of what each part means.
Your tyre size is a combination of numbers and letters like: 205/55 R16 Each part tells you something important about your tyre.
This is the first number (e.g., 205).
It shows how wide your tyre is in millimetres, from one sidewall to the other.
→ Wider tyres = more grip
→ Narrower tyres = better fuel efficiency
The sidewall is the outer side of your tyre (the part you see). This is where all the important details are printed, including size, speed rating, and load capacity.
This is the second number (e.g., 55).
It shows the height of the tyre sidewall as a percentage of the width.
→ Example:
If the profile is 55, the height is 55% of the tyre width
Lower number = sportier, less comfort
Higher number = more comfort, smoother ride
This is shown by a letter (usually R).
→ R = Radial, which is the most common type used in modern cars.
This is the last number (e.g., 16).
It tells you the size of the wheel your tyre fits, measured in inches.
A number that tells you how much weight your tyre can carry safely. Higher number = more weight capacity.
A letter that shows the maximum speed your tyre can handle safely. Each letter represents a specific speed limit
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