Home › 18" tire sizes › 255/70R18
255/70R18 tire size in inches
255/70R18 is 32.06" tall and 10.04" wide, and fits a 18" rim. In flotation (inch) sizing that is roughly 32.1x10.0R18.
255/70R18 dimensions
| Measurement | Inches | Metric |
|---|---|---|
| Overall diameter (height) | 32.06" | 814 mm |
| Section width | 10.04" | 255 mm |
| Sidewall height | 7.03" | 178.5 mm |
| Rim diameter | 18" | 457.2 mm |
| Circumference | 100.7" | 2558 mm |
| Revolutions per mile | 629 | |
| Aspect ratio | 70% (sidewall is 70% of the width) | |
Drawn to scale
Among the 122 sizes for 18" wheels on this site, 255/70R18 is #72 by height (shortest: 245/35R18, tallest: 340/80R18).
What people compare 255/70R18 with
Real comparisons drivers search for, worked out against 255/70R18:
| Compared size | Height | Width | Sidewall | Speedo at true 60 |
|---|---|---|---|---|
| 275/65R18 | +0.01" (+0.03%) | +0.79" | +0.01" | 60 mph |
| 275/70R18 | +1.10" (+3.43%) | +0.79" | +0.55" | 58 mph |
| 265/65R18 | -0.50" (-1.56%) | +0.39" | -0.25" | 61 mph |
| 265/70R18 | +0.55" (+1.72%) | +0.39" | +0.27" | 59 mph |
| 265/60R18 | -1.54" (-4.8%) | +0.39" | -0.77" | 63 mph |
| 285/70R17 | +0.65" (+2.03%) | +1.18" | +0.82" | 58.8 mph |
How the 255/70R18 numbers are worked out
The size code reads as 255 mm section width, 70% aspect ratio, R for radial construction and 18-inch wheel.
- Sidewall = 255 × 70% = 178.5 mm = 7.03"
- Diameter = 18" + 2 × 7.03" = 32.06"
- Circumference = π × 32.06" = 100.7"
- Revs per mile = 63,360" ÷ 100.7" = 629
Sizes that can replace 255/70R18 on a 18" wheel
Within 3% of 32.06". Last column: speedometer reading at a true 60 mph.
| Size | Diameter | Width | Difference | Speedo at true 60 mph |
|---|---|---|---|---|
| 275/65R18 | 32.07" | 10.83" | +0.03% | 60 mph |
| 325/55R18 | 32.07" | 12.80" | +0.03% | 60 mph |
| 295/60R18 | 31.94" | 11.61" | -0.37% | 60.2 mph |
| 235/75R18 | 31.88" | 9.25" | -0.56% | 60.3 mph |
| 270/65R18 | 31.82" | 10.63" | -0.75% | 60.5 mph |
| 280/65R18 | 32.33" | 11.02" | +0.84% | 59.5 mph |
| 305/60R18 | 32.41" | 12.01" | +1.09% | 59.4 mph |
| 245/75R18 | 32.47" | 9.65" | +1.28% | 59.2 mph |
| 265/65R18 | 31.56" | 10.43" | -1.56% | 61 mph |
| 285/65R18 | 32.59" | 11.22" | +1.65% | 59 mph |
| 265/70R18 | 32.61" | 10.43" | +1.72% | 59 mph |
| 245/70R18 | 31.50" | 9.65" | -1.75% | 61.1 mph |
One size wider or narrower
- Narrower: 245/70R18 — 9.65" wide, 31.50" tall
- Wider: 265/70R18 — 10.43" wide, 32.61" tall
Same height on a different wheel size
- 255/85R15 15" (+0.03%)
- 285/75R15 15" (-0.72%)
- 305/70R15 15" (-0.78%)
- 315/70R15 15" (+0.94%)
- 295/75R15 15" (+1.12%)
- 265/80R15 15" (-1.15%)
- 255/80R16 16" (0%)
- 315/65R16 16" (+0.19%)
- 270/75R16 16" (-0.37%)
- 275/75R16 16" (+0.56%)
Questions about 255/70R18
How tall is a 255/70R18 tire in inches?
A 255/70R18 tire is 32.06 inches (814 mm) tall: the 18-inch rim plus two sidewalls of 7.03 inches each.
Is 255/70R18 a 32 inch tire?
Yes. At 32.06 inches tall it is commonly called a 32-inch tire.
How many revolutions per mile does a 255/70R18 make?
About 629 revolutions per mile, based on a calculated circumference of 100.7 inches.
What size can replace 255/70R18?
275/65R18 is the closest match on a 18" rim (+0.03% height). Check load index, speed rating and clearance first.
Compare 255/70R18 against any other size with the tire size calculator.