How to read your tyre size.
Start with the marking on your tyre’s sidewall, then check your vehicle placard. A few numbers help you find the right place in the Rhino range.
Read a tyre marking step by step.
This is an example marking, not a recommendation for your vehicle. In 225/55R18, the first number is the nominal width, the second is the profile, and the final number is the rim diameter.
| Marking | What it means |
|---|---|
| 225 | Nominal tyre section width in millimetres. |
| 55 | Aspect ratio: the sidewall height expressed as a percentage of the nominal width. |
| R | Radial construction. |
| 18 | Nominal rim diameter in inches. |
Check the load and speed markings too.
The size is followed by further markings, often a load index and a speed symbol. Listings may also show XL, LT, run-flat or other construction and application information. These details are part of the specification, not simply model names.
Match the required tyre specification to your vehicle placard and the vehicle or tyre manufacturer’s guidance. If you are unsure about a rating, commercial marking or alternative size, ask Rhino before ordering.
Find the size to search.
- Read the sidewallLook at the tyres currently on the car. Check front and rear, as some vehicles use different sizes.
- Check the placardConfirm the required size and ratings on the vehicle’s tyre placard or in its manufacturer information.
- Search the rangeSelect width, profile and rim diameter in the Rhino tyre finder, then compare the matching listings.
A previous owner may have changed wheels or tyre sizes. If the sidewall and vehicle placard do not agree, send the details to Rhino so the setup can be checked before you buy.
Comparing an alternative tyre size?
Our tyre size calculator compares dimensions such as overall diameter, width and sidewall height. It is a comparison tool; it does not approve a replacement size for a vehicle.
Rim width, required load and speed ratings, wheel clearance and vehicle requirements still need checking. Open the tyre size calculator from the tyre page, or contact the team if you need help interpreting the result.
Good to know before you book
Where is the tyre placard?
Its position varies by vehicle. Check the door opening or pillar and the vehicle owner’s information to locate it. If you cannot find it, ask Rhino for help with the vehicle details.
What if my tyres have a different kind of marking?
Commercial and flotation tyres can use formats such as 7.50R16 or 31X10.50R15. The Rhino tyre finder includes a full-size selection for these markings. Ask us if you cannot find yours.
Can I search without choosing a car?
Yes. The tyre finder starts with size. You should still confirm the size and required ratings against your vehicle’s placard and manufacturer information.
Can a size calculator confirm that a tyre will fit?
No. A calculator compares dimensions only. Fitment, rim suitability, ratings and vehicle requirements still need to be checked.
Keep exploring
Ready for your next set?
Start with your tyre size or vehicle. Rhino can help with the details.