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Understanding tyre sizes
205/55 R16 91V — six entries in one line. What each of them means, where it stands and which one is binding.
Where you find your size
The information is written on the side of the tyre, approximately 205/55 R16 91V. The easiest way to read it is to look at the tyre that is currently on the car.
There is no tyre size in the vehicle registration document - there you will only find the type approval number under number 24. It describes exactly your vehicle version and the permitted sizes depend on it. Enter it into our search and we will show it to you.
Only sizes approved for your vehicle may be installed. What these are is not stated in the vehicle registration document, but in the type approval - the number under number 24 leads there. Anything beyond that requires a report and an entry in the vehicle registration document.
Our search only shows approved sizes - anything that doesn't fit doesn't even appear.
What 205/55 R16 91V means
The symbols on the sidewall are not a secret code. Select a symbol and the diagram shows the corresponding measurement.
Tread width
The tread width in millimetres. A wider tyre offers more cornering grip, but also more rolling resistance and usually more noise.
205mm '= 20.5 cmYou don't have to know this by heart: enter your vehicle or the registration number in the search and we'll do it. Find the type approval number →
Load index: how much weight a tyre can carry
The index represents a weight per tyre, not the permissible axle load of the vehicle. An excerpt from the standardized table — the common values for passenger cars.
| Index | Per tyre | Each axle (two tyres) |
|---|---|---|
| 75 | 387kg | 774kg |
| 80 | 450kg | 900kg |
| 84 | 500kg | 1,000 kg |
| 88 | 560kg | 1,120 kg |
| 91 | 615kg | 1,230 kg |
| 94 | 670kg | 1,340 kg |
| 97 | 730kg | 1,460 kg |
| 99 | 775kg | 1,550 kg |
| 101 | 825kg | 1,650 kg |
| 104 | 900kg | 1,800 kg |
| 107 | 975kg | 1,950 kg |
| 110 | 1,060 kg | 2,120 kg |
Speed rating: the maximum approved speed
A higher index than the released one is allowed, a lower one is not.
| Index | Approved up to |
|---|---|
| Q | 160 km/h |
| R | 170 km/h |
| S | 180 km/h |
| T | 190 km/h |
| H | 210 km/h |
| V | 240 km/h |
| W | 270 km/h |
| Y | 300 km/h |
| (Y) | over 300 km/h |
Winter tyres may have a lower speed index than that approved for your vehicle - but then a notice must be stuck in the driver's field of vision. This exception does not apply to the load index.
Why the size cannot be chosen freely
Width, cross section and rim diameter together result in the outside diameter of the wheel. If it changes, everything that depends on it changes: the speedometer display, the gear ratio, the distance to the wheel arch.
That is why type approval does not allow arbitrary combinations, but rather a manageable list. If you want a wider tread, you usually have to reduce the cross section at the same time so that the diameter is correct.
Tyre sizes in our range
- Available tyre sizes
- 309
- Rim diameter
- 14 to 23 inches
- Tyres in the range
- 26,834
- Brands
- 71
- Seasons
- 205/55 R16
Further reading
Load and speed index follow standardized tables that do not change; The excerpts shown here come from the same table that the theme uses to convert the values on each tyre. The catalog information is updated after each inventory comparison.