255/50R19 Tyre Size — Dimensions & Alternatives
Get full dimensions for 255/50R19 tires. Common on luxury SUVs.
255/50R19 dimensions
| Section width | 255mm |
| Aspect ratio | 50% |
| Sidewall height | 128mm (5.04in) |
| Rim diameter | 19" (482.6mm) |
| Overall diameter | 739mm (29.09in) |
| Circumference | 2322mm |
| Revs per km | 431 |
What does 255/50R19 mean?
The tyre designation 255/50R19 breaks down into three parts: the section width (255mm — how wide the tread is), the aspect ratio (50% — sidewall height as a percentage of width), and the rim diameter (19 inches). The "R" indicates radial construction, which is standard on nearly every passenger vehicle today.
Can I fit an alternative size?
Yes — tyres with a slightly different section width, aspect ratio or rim size can often be fitted safely provided the overall diameter stays within about 3% of the original. Going wider improves grip but increases rolling resistance; going narrower reduces road noise and fuel consumption. The lookup tool below shows compatible alternative sizes for 255/50R19.
Speedometer error
Changing tyre size affects your speedometer reading. A larger overall diameter means the speedometer under-reads (you're actually going faster than the needle shows); a smaller diameter means it over-reads. Stay within 3% to keep the error under the legal tolerance in Australia and New Zealand.
