305/35R20 tire size
A 305/35R20 tire is 28.41 inches (721.5 mm) tall, 12.01 in (305 mm) wide and fits a 20-inch wheel. In inch notation it is roughly a 28.4x12.0R20 — a "28-inch" tire.
| Overall diameter | 28.41 in | 721.5 mm |
|---|---|---|
| Section width | 12.01 in | 305 mm |
| Sidewall height | 4.20 in | 106.8 mm |
| Circumference | 89.24 in | 2,267 mm |
| Revolutions | 710.0 per mile | 441.2 per km |
| Rim diameter | 20 in | 508.0 mm |
Compare 305/35R20 with another size
Alternative sizes on the same 20-inch wheel
Sizes in use within ±3 % of the overall diameter of 305/35R20:
Plus and minus sizes for 305/35R20
| Size | Wheel | Diameter | Difference |
|---|---|---|---|
| 285/45R18 | Minus 2 (18 in) | 28.10 in | −1.08% |
| 275/45R18 | Minus 2 (18 in) | 27.74 in | −2.33% |
| 285/50R18 | Minus 2 (18 in) | 29.22 in | +2.87% |
| 345/35R19 | Minus 1 (19 in) | 28.51 in | +0.36% |
| 295/40R19 | Minus 1 (19 in) | 28.29 in | −0.40% |
| 275/45R19 | Minus 1 (19 in) | 28.74 in | +1.19% |
| 285/40R19 | Minus 1 (19 in) | 27.98 in | −1.51% |
| 315/30R21 | Plus 1 (21 in) | 28.44 in | +0.12% |
| 275/35R21 | Plus 1 (21 in) | 28.58 in | +0.61% |
| 305/30R21 | Plus 1 (21 in) | 28.20 in | −0.71% |
| 325/30R21 | Plus 1 (21 in) | 28.68 in | +0.96% |
| 285/30R22 | Plus 2 (22 in) | 28.73 in | +1.15% |
| 295/30R22 | Plus 2 (22 in) | 28.97 in | +1.98% |
| 355/25R22 | Plus 2 (22 in) | 28.99 in | +2.05% |
| 305/30R22 | Plus 2 (22 in) | 29.20 in | +2.81% |
Vehicles approved with 305/35R20 tires
Models whose Swiss type approval lists 305/35R20 as a standard or optional size (76 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 305/35R20 size
- 305 — section width in millimetres (12.01 in).
- 35 — aspect ratio: the sidewall is 35 % of the width, 106.8 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.