285/40R23 tire size
A 285/40R23 tire is 31.98 inches (812.2 mm) tall, 11.22 in (285 mm) wide and fits a 23-inch wheel. In inch notation it is roughly a 32.0x11.2R23 — a "32-inch" tire.
| Overall diameter | 31.98 in | 812.2 mm |
|---|---|---|
| Section width | 11.22 in | 285 mm |
| Sidewall height | 4.49 in | 114.0 mm |
| Circumference | 100.46 in | 2,552 mm |
| Revolutions | 630.7 per mile | 391.9 per km |
| Rim diameter | 23 in | 584.2 mm |
Compare 285/40R23 with another size
Alternative sizes on the same 23-inch wheel
Sizes in use within ±3 % of the overall diameter of 285/40R23:
Plus and minus sizes for 285/40R23
| Size | Wheel | Diameter | Difference |
|---|---|---|---|
| 275/50R21 | Minus 2 (21 in) | 31.83 in | −0.47% |
| 325/40R21 | Minus 2 (21 in) | 31.24 in | −2.31% |
| 285/45R21 | Minus 2 (21 in) | 31.10 in | −2.75% |
| 255/50R21 | Minus 2 (21 in) | 31.04 in | −2.93% |
| 285/45R22 | Minus 1 (22 in) | 32.10 in | +0.38% |
| 275/45R22 | Minus 1 (22 in) | 31.74 in | −0.73% |
| 325/40R22 | Minus 1 (22 in) | 32.24 in | +0.81% |
| 305/40R22 | Minus 1 (22 in) | 31.61 in | −1.16% |
Vehicles approved with 285/40R23 tires
Models whose Swiss type approval lists 285/40R23 as a standard or optional size (175 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 23-inch sizes
Reading the 285/40R23 size
- 285 — section width in millimetres (11.22 in).
- 40 — aspect ratio: the sidewall is 40 % of the width, 114.0 mm.
- R — radial construction (ZR on the sidewall means a high-speed rated radial; the dimensions are the same).
- 23 — fits a 23-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.