28.0" tall, 9.3" wide, 6.5" sidewall
A 235/70R15 tire is 28.0 inches (710 mm) tall and 9.3 inches wide. The sidewall is 70% of the width, 6.5 inches, on a 15-inch wheel, and the tire turns about 722 times per mile.
In flotation terms that is about 28.0x9.3R15. People often call it a 28-inch tire.
The size most often compared with it is 235/75R15, which is 0.9" taller (+3.3%). At an indicated 60 mph you would be doing 62.0 mph on it, more than the 3% change many shops use as a limit.
| Current | New | Difference |
|---|
| Shows | Actual speed |
|---|
Same 15" wheel, within 20 mm of width and 10 points of aspect ratio.
| Size | Diameter | Width | Sidewall | vs 235/70R15 | |
|---|---|---|---|---|---|
| 255/65R15 | 28.1" | 10.0" | 6.5" | +0.4% | |
| 215/75R15 | 27.7" | 8.5" | 6.3" | −0.9% | |
| 225/70R15 | 27.4" | 8.9" | 6.2" | −2.0% | |
| 245/70R15 | 28.5" | 9.6" | 6.8" | +2.0% | |
| 215/80R15 | 28.5" | 8.5" | 6.8" | +2.1% | |
| 255/60R15 | 27.0" | 10.0" | 6.0" | −3.2% | |
| 235/65R15 | 27.0" | 9.3" | 6.0" | −3.3% | |
| 235/75R15 | 28.9" | 9.3" | 6.9" | +3.3% | compare |
| 215/70R15 | 26.9" | 8.5" | 5.9" | −3.9% | |
| 255/70R15 | 29.1" | 10.0" | 7.0" | +3.9% |
Sizes within 2% of 28.0" on 17" wheels.
| Size | Diameter | Width | Sidewall | vs 235/70R15 | |
|---|---|---|---|---|---|
| 275/50R17 | 27.8" | 10.8" | 5.4" | −0.5% | |
| 245/55R17 | 27.6" | 9.6" | 5.3" | −1.2% | |
| 205/65R17 | 27.5" | 8.1" | 5.2" | −1.6% | |
| 265/50R17 | 27.4" | 10.4" | 5.2" | −1.9% |
Actual speed when the speedometer is calibrated for 235/70R15.
| Speedometer shows | on 235/75R15 | on 275/60R15 | on 255/65R15 |
|---|---|---|---|
| 30 mph | 31.0 mph | 30.0 mph | 30.1 mph |
| 45 mph | 46.5 mph | 45.1 mph | 45.2 mph |
| 60 mph | 62.0 mph | 60.1 mph | 60.2 mph |
| 70 mph | 72.3 mph | 70.1 mph | 70.2 mph |
28.0 inches (710 mm). The sidewall is 6.5 inches.
9.3 inches (235 mm) section width, measured sidewall to sidewall.
About 28.0x9.3R15.
235/75R15 is +3.3% in diameter, more than the common 3% guideline, so expect a speedometer error and check clearance. It is 0.0" wider.