345/30R21 tire size
A 345/30R21 tire is 29.15 inches (740.4 mm) tall, 13.58 in (345 mm) wide and fits a 21-inch wheel. In inch notation it is roughly a 29.1x13.6R21 — a "29-inch" tire.
| Overall diameter | 29.15 in | 740.4 mm |
|---|---|---|
| Section width | 13.58 in | 345 mm |
| Sidewall height | 4.07 in | 103.5 mm |
| Circumference | 91.58 in | 2,326 mm |
| Revolutions | 691.9 per mile | 429.9 per km |
| Rim diameter | 21 in | 533.4 mm |
Compare 345/30R21 with another size
Alternative sizes on the same 21-inch wheel
Sizes in use within ±3 % of the overall diameter of 345/30R21:
Plus and minus sizes for 345/30R21
Vehicles approved with 345/30R21 tires
Models whose Swiss type approval lists 345/30R21 as a standard or optional size (16 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 21-inch sizes
Reading the 345/30R21 size
- 345 — section width in millimetres (13.58 in).
- 30 — aspect ratio: the sidewall is 30 % of the width, 103.5 mm.
- R — radial construction (ZR on the sidewall means a high-speed rated radial; the dimensions are the same).
- 21 — fits a 21-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.