255/65R18 Tire Size
Dimensions of a 255/65R18 tire in inches and millimeters, with equivalent and plus sizes.
255/65R18 dimensions
A 255/65R18 tire is 255 mm wide with a sidewall that is 65% of the width (166 mm), mounted on a 18-inch rim. Its overall diameter is about 31.05 inches (789 mm), so it is roughly a 31.1-inch tall tire.
| Overall diameter | 31.05 in | 789 mm |
|---|---|---|
| Section width | 10.04 in | 255 mm |
| Sidewall height | 6.53 in | 165.8 mm |
| Rim diameter | 18 in | 457 mm |
| Circumference | 97.6 in | 2478 mm |
| Revolutions | 650 per mile | 404 per km |
Equivalent sizes on a 18-inch rim
These sizes stay within ±3% of the 255/65R18 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 |
|---|---|---|---|
| 275/60R18 | 30.99 in | 787 mm | -0.2% |
| 235/70R18 | 30.95 in | 786 mm | -0.3% |
| 245/70R18 | 31.50 in | 800 mm | +1.5% |
| 245/65R18 | 30.54 in | 776 mm | -1.6% |
| 265/65R18 | 31.56 in | 802 mm | +1.6% |
| 265/60R18 | 30.52 in | 775 mm | -1.7% |
| 235/75R18 | 31.88 in | 810 mm | +2.7% |
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 |
|---|---|---|---|
| 255/70R17 | 31.06 in | 789 mm | +0.0% |
| 255/60R19 | 31.05 in | 789 mm | -0.0% |
| 255/55R20 | 31.04 in | 788 mm | -0.0% |
| 275/65R17 | 31.07 in | 789 mm | +0.1% |
| 275/55R19 | 30.91 in | 785 mm | -0.5% |
| 285/50R20 | 31.22 in | 793 mm | +0.5% |
| 275/50R20 | 30.83 in | 783 mm | -0.7% |
| 285/55R19 | 31.34 in | 796 mm | +0.9% |
| 245/75R17 | 31.47 in | 799 mm | +1.3% |
| 265/55R20 | 31.48 in | 800 mm | +1.4% |
Compare 255/65R18 with another size →
Frequently asked questions
How tall is a 255/65R18 tire?
About 31.05 inches (789 mm) in overall diameter.
How wide is a 255/65R18 tire?
The section width is 255 mm, about 10.0 inches.
What size can replace 255/65R18?
On the same rim, 275/60R18 is the closest size (-0.2% diameter). Use only sizes approved for your vehicle.
How many revolutions per mile does a 255/65R18 tire make?
About 650 revolutions per mile (404 per km).
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