The dimensions are stated on all car tyres. Example of designation: 235/60 R18 103 V.
| 235 | Tyre width (mm) |
| 60 | Ratio between tyre wall height and tyre width (%) |
| R | Radial ply |
| 18 | Rim diameter in inches |
| 103 | Codes for the maximum permitted tyre load, tyre load index (LI) |
| V | Speed rating for maximum permitted speed, speed rating (SS). (In this case 240 km/h (149 mph).) |
The car has an approval for the complete vehicle with certain combinations of wheel rims and tyres.