32.7" tall, 9.3" wide, 7.9" sidewall
A 235/85R17 tire is 32.7 inches (831 mm) tall and 9.3 inches wide. The sidewall is 85% of the width, 7.9 inches, on a 17-inch wheel, and the tire turns about 616 times per mile.
In flotation terms that is about 32.7x9.3R17, closest to the common 33x12.50R17 (33.0"). People often call it a 33-inch tire.
The size most often compared with it is 245/80R17, which is 0.3" shorter (−0.9%). At an indicated 60 mph you would be doing 59.5 mph on it.
| Current | New | Difference |
|---|
| Shows | Actual speed |
|---|
Same 17" wheel, within 20 mm of width and 10 points of aspect ratio.
| Size | Diameter | Width | Sidewall | vs 235/85R17 | |
|---|---|---|---|---|---|
| 245/80R17 | 32.4" | 9.6" | 7.7" | −0.9% | |
| 255/80R17 | 33.1" | 10.0" | 8.0" | +1.0% | |
| 245/85R17 | 33.4" | 9.6" | 8.2" | +2.0% | |
| 255/75R17 | 32.1" | 10.0" | 7.5" | −2.0% | |
| 235/80R17 | 31.8" | 9.3" | 7.4" | −2.8% | |
| 245/75R17 | 31.5" | 9.6" | 7.2" | −3.8% | |
| 255/85R17 | 34.1" | 10.0" | 8.5" | +4.1% | |
| 225/80R17 | 31.2" | 8.9" | 7.1" | −4.8% | |
| 225/75R17 | 30.3" | 8.9" | 6.6" | −7.5% |
Sizes within 2% of 32.7" on 15" or 16" or 18" wheels.
| Size | Diameter | Width | Sidewall | vs 235/85R17 | |
|---|---|---|---|---|---|
| 265/85R15 | 32.7" | 10.4" | 8.9" | +0.0% | |
| 265/80R16 | 32.7" | 10.4" | 8.3" | −0.1% | |
| 235/80R18 | 32.8" | 9.3" | 7.4" | +0.2% | |
| 305/70R16 | 32.8" | 12.0" | 8.4" | +0.3% | |
| 285/75R16 | 32.8" | 11.2" | 8.4" | +0.3% | |
| 265/70R18 | 32.6" | 10.4" | 7.3" | −0.4% |
Actual speed when the speedometer is calibrated for 235/85R17.
| Speedometer shows | on 245/80R17 | on 255/80R17 | on 245/85R17 |
|---|---|---|---|
| 30 mph | 29.7 mph | 30.3 mph | 30.6 mph |
| 45 mph | 44.6 mph | 45.5 mph | 45.9 mph |
| 60 mph | 59.5 mph | 60.6 mph | 61.2 mph |
| 70 mph | 69.4 mph | 70.7 mph | 71.4 mph |
32.7 inches (831 mm). The sidewall is 7.9 inches.
9.3 inches (235 mm) section width, measured sidewall to sidewall.
About 32.7x9.3R17; the closest common flotation size is 33x12.50R17 at 33.0".
245/80R17 is −0.9% in diameter, within the common 3% guideline. It is 0.4" wider.