225/55R18 tire size
A 225/55R18 tire is 27.74 inches (704.7 mm) tall, 8.86 in (225 mm) wide and fits a 18-inch wheel. In inch notation it is roughly a 27.7x8.9R18 — a "28-inch" tire.
| Overall diameter | 27.74 in | 704.7 mm |
|---|---|---|
| Section width | 8.86 in | 225 mm |
| Sidewall height | 4.87 in | 123.8 mm |
| Circumference | 87.16 in | 2,214 mm |
| Revolutions | 726.9 per mile | 451.7 per km |
| Rim diameter | 18 in | 457.2 mm |
Compare 225/55R18 with another size
Alternative sizes on the same 18-inch wheel
Sizes in use within ±3 % of the overall diameter of 225/55R18:
Plus and minus sizes for 225/55R18
| Size | Wheel | Diameter | Difference |
|---|---|---|---|
| 215/70R16 | Minus 2 (16 in) | 27.85 in | +0.38% |
| 245/60R16 | Minus 2 (16 in) | 27.57 in | −0.61% |
| 225/65R16 | Minus 2 (16 in) | 27.52 in | −0.82% |
| 235/65R16 | Minus 2 (16 in) | 28.03 in | +1.02% |
| 225/60R17 | Minus 1 (17 in) | 27.63 in | −0.41% |
| 245/55R17 | Minus 1 (17 in) | 27.61 in | −0.48% |
| 205/65R17 | Minus 1 (17 in) | 27.49 in | −0.91% |
| 215/65R17 | Minus 1 (17 in) | 28.00 in | +0.94% |
| 245/45R19 | Plus 1 (19 in) | 27.68 in | −0.23% |
| 275/40R19 | Plus 1 (19 in) | 27.66 in | −0.30% |
| 225/50R19 | Plus 1 (19 in) | 27.86 in | +0.41% |
| 205/55R19 | Plus 1 (19 in) | 27.88 in | +0.48% |
| 245/40R20 | Plus 2 (20 in) | 27.72 in | −0.10% |
| 195/50R20 | Plus 2 (20 in) | 27.68 in | −0.24% |
| 215/45R20 | Plus 2 (20 in) | 27.62 in | −0.45% |
| 275/35R20 | Plus 2 (20 in) | 27.58 in | −0.60% |
| 245/35R21 | Plus 3 (21 in) | 27.75 in | +0.03% |
| 275/30R21 | Plus 3 (21 in) | 27.50 in | −0.89% |
| 255/35R21 | Plus 3 (21 in) | 28.03 in | +1.02% |
| 265/30R21 | Plus 3 (21 in) | 27.26 in | −1.75% |
Vehicles approved with 225/55R18 tires
Models whose Swiss type approval lists 225/55R18 as a standard or optional size (3,171 approvals in total). Always check your own vehicle's placard or papers.
- Audi A6
- Audi A7
- BMW X1
- Peugeot 3008
- Peugeot 5008
- Citroen C5
- DS DS7
- Jeep Renegade
- Jeep Cherokee
- Jeep Compass
- Opel Grandland X
- Hyundai ix35
- Mitsubishi Outlander
- SsangYong Korando
- Opel Grandland
- BMW 5 Series
- Renault Koleos
- DS DS4
- Kia Sportage
- BMW X2
- Subaru Forester
- MINI Countryman
- Citroen C-Crosser
- Peugeot 4007
- Volvo EX30
- BMW iX1
- Mitsubishi Eclipse Cross
- Hyundai Ioniq
- Mitsubishi ASX
- Nissan X-Trail
- Citroen C4 Aircross
- Mitsubishi Eclipse
- Honda ZR-V
- Hyundai Tucson
- Suzuki E
- Toyota C-HR
- Citroen C4
- DS 7
- MG S5
- Peugeot 4008
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 18-inch sizes
- 205/45R18 (−8.9%)
- 205/55R18 (−3.1%)
- 205/60R18 (−0.2%)
- 215/45R18 (−7.7%)
- 215/50R18 (−4.6%)
- 215/55R18 (−1.6%)
- 215/60R18 (+1.5%)
- 225/45R18 (−6.4%)
- 225/50R18 (−3.2%)
- 225/60R18 (+3.2%)
- 235/45R18 (−5.1%)
- 235/50R18 (−1.8%)
- 235/55R18 (+1.6%)
- 235/60R18 (+4.9%)
- 235/65R18 (+8.2%)
- 245/45R18 (−3.8%)
- 245/50R18 (−0.4%)
- 245/60R18 (+6.6%)
- 245/65R18 (+10.1%)
Reading the 225/55R18 size
- 225 — section width in millimetres (8.86 in).
- 55 — aspect ratio: the sidewall is 55 % of the width, 123.8 mm.
- R — radial construction (ZR on the sidewall means a high-speed rated radial; the dimensions are the same).
- 18 — fits a 18-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.