How to Find Your Tyre Size
(Sidewall, Reg & Vehicle Guide)
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Discover Your Tyre Size by Registration
Alternatively, you can easily determine the suitable tyre sizes for your vehicle with our convenient vehicle registration lookup tool. This tool will provide you with a list of potential tyre sizes that could match your vehicle; however, it’s essential to verify and select the correct size. To begin, enter your vehicle registration below.
If you’re still looking for help and advice on how to find your tyre size, get in touch with our expert team by email, chat or phone and we’ll be glad to help. Get in touch with our pro team for expert advice.
Finding your tyre size is essential for safe fitment, proper handling, and optimal performance. Whether you’re replacing worn tyres or upgrading your setup, knowing the correct tyre size helps you choose the right option for your vehicle.
You can find your tyre size in three main places:
- On the tyre sidewall – the most common and accurate method
- Inside the driver’s door frame or on the fuel cap
- In your vehicle handbook
The tyre sidewall will show a code like 205/55R16. This series of numbers and letters represents the tyre’s width, profile, construction, and rim diameter.
Here’s what each part means:
- Tyre Width: The first three digits represent the width of the tyre in millimetres. For example, 205 means the tyre is 205 mm wide.
- Aspect Ratio: The next two digits show the sidewall height as a percentage of the width. In 205/55R16, the sidewall height is 55% of the tyre width.
- Construction: The letter indicates how the tyre is built. Most modern tyres use “R” for radial construction.
- Rim Diameter: The final number shows the wheel size in inches. For example, R16 means the tyre fits a 16-inch wheel.
It’s important to choose the correct tyre size for your specific vehicle, as requirements vary by make, model, and year. You should always check your vehicle handbook or consult a tyre specialist if unsure.
Alongside size, factors such as load rating, speed rating, and tread pattern also play a key role in safety and performance.
Check Your Tyre Sidewall
The easiest way to find your tyre size is to check the sidewall of your current tyres.
Look for a code like this: 265/65R17 120S.
• The first part (265/65R17) is your tyre size
• The second part (120S) is the load and speed ratings
This code tells you everything you need to know to choose the correct replacement tyres.
What Do Tyre Size Numbers Mean?
Let’s break down a typical tyre size: 265/65R17.
• 265 – Tyre Width
This is the tyre’s width in millimetres. In this example, the tyre is 265 mm wide.
• 65 – Aspect Ratio
This is the sidewall height as a percentage of the tyre width. Here, the sidewall height is 65% of 265 mm.
• R – Construction
This indicates radial construction, which is standard for almost all modern tyres.
• 17 – Rim Diameter
This is the wheel size in inches. In this example, the tyre fits a 17-inch wheel.
Understanding these numbers helps you choose the correct tyre size and ensures a proper fit for your vehicle.
Why Tyre Load Ratings Are Important
The tyre load rating appears alongside the tyre size as part of a code such as 120S.
• The number (120) = load rating
• The letter (S) = speed rating
The load rating indicates the maximum weight each tyre can safely carry. Choosing the correct load rating is essential, especially for vans, pickups, and vehicles carrying heavy loads.
Using tyres with an incorrect load rating can:
• Affect handling and stability
• Increase tyre wear
• Invalidate insurance in some cases
For example, a tyre with a load rating of 120 can carry up to 1400kg per tyre.
To find the correct load rating for your vehicle, check your current tyres or consult your vehicle handbook.
Use the table below to convert load ratings to the maximum weight per tyre:
| Load index no. | Max tyre load (kg) | Load index no. | Max tyre load (kg) |
|---|---|---|---|
| 62 | 265 | 95 | 690 |
| 63 | 272 | 96 | 710 |
| 64 | 280 | 97 | 730 |
| 65 | 290 | 98 | 750 |
| 66 | 300 | 99 | 775 |
| 67 | 307 | 100 | 800 |
| 68 | 315 | 101 | 825 |
| 69 | 325 | 102 | 850 |
| 70 | 335 | 103 | 875 |
| 71 | 345 | 104 | 900 |
| 72 | 355 | 105 | 925 |
| 73 | 365 | 106 | 950 |
| 74 | 375 | 107 | 975 |
| 75 | 387 | 108 | 1000 |
| 76 | 400 | 109 | 1030 |
| 77 | 412 | 110 | 1060 |
| 78 | 425 | 111 | 1090 |
| 79 | 437 | 112 | 1120 |
| 80 | 450 | 113 | 1150 |
| 81 | 462 | 114 | 1180 |
| 82 | 475 | 115 | 1215 |
| 83 | 487 | 116 | 1250 |
| 84 | 500 | 117 | 1285 |
| 85 | 515 | 118 | 1320 |
| 86 | 530 | 119 | 1360 |
| 87 | 545 | 120 | 1400 |
| 88 | 560 | 121 | 1450 |
| 89 | 580 | 122 | 1500 |
| 90 | 600 | 123 | 1550 |
| 91 | 615 | 124 | 1600 |
| 92 | 630 | 125 | 1650 |
| 93 | 650 | 126 | 1700 |
| 94 | 670 |
Why Tyre Speed Ratings Matter
The tyre speed rating appears as a letter at the end of the tyre code, for example, 120S.
• The number (120) = load rating
• The letter (S) = speed rating
The speed rating indicates the maximum speed a tyre can safely handle.
Using tyres with an incorrect speed rating can:
• Reduce handling and performance
• Increase the risk at higher speeds
• Invalidate insurance in some cases
For example, a tyre with an S rating is approved for speeds up to 112 mph.
To find the correct speed rating for your vehicle, check your current tyres or consult your vehicle handbook.
Use the table below to understand speed ratings and their maximum limits:
Higher-performance vehicles require tyres with higher speed ratings to ensure safe handling at high speeds.
| Speed rating | Max speed (mph) |
|---|---|
| N | 87 |
| P | 93 |
| Q | 99 |
| R | 106 |
| S | 112 |
| T | 118 |
| U | 124 |
| H | 130 |
| V | 149 |
| Z | 150 |
| W | 168 |
| Y | 186 |
Tyre Size Exceptions (Imperial & Off-Road Sizes)
While most tyres follow a standard metric format, there are exceptions.
• Classic 4×4 & Land Rover tyres
These are often listed in imperial sizing, such as 6.00/16 or 7.50/16.
The second number (16) is the rim diameter in inches, while 6.00 or 7.50 indicates the tyre width in inches.
• Large off-road tyres
Oversized off-road tyres are often shown in inch sizing, such as 40/13.5R17.
The first number (40) is the overall tyre diameter in inches, the second (13.5) is the width, and the final number (17) is the wheel size.
Understanding these formats is important when selecting tyres for classic vehicles or off-road builds.
Find the Right Tyres for Your Vehicle
Choosing the correct tyre size ensures a safe fit, proper handling, and optimal performance. Whether you’re replacing worn tyres or upgrading your setup, the right size makes all the difference.
Browse tyres by size, or use our registration lookup tool to find the right fit for your vehicle. Expert advice is available to help you choose with confidence.
All tyres are available with UK-wide delivery or professional fitting, making it easy to get the right setup for your vehicle.
