175/55R20 tire size
A 175/55R20 tire is 27.58 inches (700.5 mm) tall, 6.89 in (175 mm) wide and fits a 20-inch wheel. In inch notation it is roughly a 27.6x6.9R20 — a "28-inch" tire.
| Overall diameter | 27.58 in | 700.5 mm |
|---|---|---|
| Section width | 6.89 in | 175 mm |
| Sidewall height | 3.79 in | 96.3 mm |
| Circumference | 86.64 in | 2,201 mm |
| Revolutions | 731.3 per mile | 454.4 per km |
| Rim diameter | 20 in | 508.0 mm |
Compare 175/55R20 with another size
Alternative sizes on the same 20-inch wheel
Sizes in use within ±3 % of the overall diameter of 175/55R20:
Plus and minus sizes for 175/55R20
| Size | Wheel | Diameter | Difference |
|---|---|---|---|
| 205/60R18 | Minus 2 (18 in) | 27.69 in | +0.39% |
| 225/55R18 | Minus 2 (18 in) | 27.74 in | +0.60% |
| 215/55R18 | Minus 2 (18 in) | 27.31 in | −0.97% |
| 195/60R18 | Minus 2 (18 in) | 27.21 in | −1.33% |
| 155/70R19 | Minus 1 (19 in) | 27.54 in | −0.13% |
| 215/50R19 | Minus 1 (19 in) | 27.46 in | −0.41% |
| 195/55R19 | Minus 1 (19 in) | 27.44 in | −0.49% |
| 225/50R19 | Minus 1 (19 in) | 27.86 in | +1.01% |
Vehicles approved with 175/55R20 tires
Models whose Swiss type approval lists 175/55R20 as a standard or optional size (32 approvals in total). Always check your own vehicle's placard or papers.
Source: Swiss Federal Roads Office (FEDRO/ASTRA), open government data. Original data (downloaded 2026-09-29). Data processed by us; errors in processing are ours, not the publisher's.
Nearby 20-inch sizes
Reading the 175/55R20 size
- 175 — section width in millimetres (6.89 in).
- 55 — aspect ratio: the sidewall is 55 % of the width, 96.3 mm.
- R — radial construction (ZR on the sidewall means a high-speed rated radial; the dimensions are the same).
- 20 — fits a 20-inch diameter wheel.
The load index and speed rating (for example 91V) follow the size on the sidewall. They must meet at least the values on your vehicle's tire placard.