235/55R18 Tire Size
Dimensions of a 235/55R18 tire in inches and millimeters, with equivalent and plus sizes.
235/55R18 dimensions
A 235/55R18 tire is 235 mm wide with a sidewall that is 55% of the width (129 mm), mounted on a 18-inch rim. Its overall diameter is about 28.18 inches (716 mm), so it is roughly a 28.2-inch tall tire.
| Overall diameter | 28.18 in | 716 mm |
|---|---|---|
| Section width | 9.25 in | 235 mm |
| Sidewall height | 5.09 in | 129.2 mm |
| Rim diameter | 18 in | 457 mm |
| Circumference | 88.5 in | 2248 mm |
| Revolutions | 716 per mile | 445 per km |
Equivalent sizes on a 18-inch rim
These sizes stay within ±3% of the 235/55R18 diameter on the same rim — the range most tire shops use. Not every size is made in every tire model, and only sizes approved for your vehicle (with the right load and speed rating) should be fitted.
| Size | Diameter | mm | Difference |
|---|---|---|---|
| 215/60R18 | 28.16 in | 715 mm | -0.1% |
| 255/50R18 | 28.04 in | 712 mm | -0.5% |
| 225/55R18 | 27.74 in | 705 mm | -1.5% |
| 245/55R18 | 28.61 in | 727 mm | +1.5% |
| 225/60R18 | 28.63 in | 727 mm | +1.6% |
| 245/50R18 | 27.65 in | 702 mm | -1.9% |
| 215/65R18 | 29.00 in | 737 mm | +2.9% |
Plus and minus sizes
Changing the rim size? These options on 17-, 19- and 20-inch rims keep the overall diameter within ±3%.
| Size | Diameter | mm | Difference |
|---|---|---|---|
| 235/50R19 | 28.25 in | 718 mm | +0.3% |
| 235/60R17 | 28.10 in | 714 mm | -0.3% |
| 255/55R17 | 28.04 in | 712 mm | -0.5% |
| 255/45R19 | 28.04 in | 712 mm | -0.5% |
| 255/40R20 | 28.03 in | 712 mm | -0.5% |
| 235/45R20 | 28.33 in | 720 mm | +0.5% |
| 265/40R20 | 28.35 in | 720 mm | +0.6% |
| 225/45R20 | 27.97 in | 710 mm | -0.7% |
| 265/45R19 | 28.39 in | 721 mm | +0.8% |
| 265/55R17 | 28.48 in | 723 mm | +1.1% |
Compare 235/55R18 with another size →
Frequently asked questions
How tall is a 235/55R18 tire?
About 28.18 inches (716 mm) in overall diameter.
How wide is a 235/55R18 tire?
The section width is 235 mm, about 9.3 inches.
What size can replace 235/55R18?
On the same rim, 215/60R18 is the closest size (-0.1% diameter). Use only sizes approved for your vehicle.
How many revolutions per mile does a 235/55R18 tire make?
About 716 revolutions per mile (445 per km).
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