215/45R18 tire size
A 215/45R18 tire is 215 mm wide with a sidewall 45% of its width (96.8 mm), fits a 18-inch rim and has an overall diameter of 651 mm (25.6 in).
| Dimension | Metric | Imperial |
|---|---|---|
| Section width | 215 mm | 8.46 in |
| Sidewall height | 96.8 mm | 3.81 in |
| Rim diameter | 457.2 mm | 18 in |
| Overall diameter | 650.7 mm | 25.62 in |
| Circumference | 2,044.2 mm | 80.48 in |
| Revolutions | 489 per km | 787 per mile |
Reading the size 215/45R18
215Width in mm45Aspect ratio (sidewall % of width)RRadial construction18Rim diameter in inches
The load index and speed rating (for example 91V) follow the size on the sidewall. Replacement tires should match or exceed the original load index and speed rating.
Alternative sizes within 3% of 215/45R18
A replacement size should stay within about 3% of the original diameter so the speedometer, ABS and transmission stay accurate. Always check clearance, load index and the vehicle manufacturer's approved sizes.
| Size | Diameter | Difference | Speedo reads 100 → actual | |
|---|---|---|---|---|
| 245/45R17 | 652 mm | +0.2% | 100.2 | Compare |
| 205/60R16 | 652 mm | +0.3% | 100.3 | Compare |
| 245/40R18 | 653 mm | +0.4% | 100.4 | Compare |
| 225/55R16 | 654 mm | +0.5% | 100.5 | Compare |
| 205/65R15 | 648 mm | -0.5% | 99.5 | Compare |
| 245/35R19 | 654 mm | +0.5% | 100.5 | Compare |
| 235/35R19 | 647 mm | -0.6% | 99.4 | Compare |
| 215/50R17 | 647 mm | -0.6% | 99.4 | Compare |
Compare 215/45R18 with any size →