29.4" tall, 12.4" wide, 6.2" sidewall
A 315/50R17 tire is 29.4 inches (747 mm) tall and 12.4 inches wide. The sidewall is 50% of the width, 6.2 inches, on a 17-inch wheel, and the tire turns about 686 times per mile.
In flotation terms that is about 29.4x12.4R17. People often call it a 29-inch tire.
The size most often compared with it is 305/55R17, which is 0.8" taller (+2.7%). At an indicated 60 mph you would be doing 61.6 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 315/50R17 | |
|---|---|---|---|---|---|
| 305/55R17 | 30.2" | 12.0" | 6.6" | +2.7% | |
| 325/45R17 | 28.5" | 12.8" | 5.8" | −3.0% | |
| 315/55R17 | 30.6" | 12.4" | 6.8" | +4.2% | |
| 305/60R17 | 31.4" | 12.0" | 7.2" | +6.8% | |
| 315/60R17 | 31.9" | 12.4" | 7.4" | +8.4% | |
| 305/40R17 | 26.6" | 12.0" | 4.8" | −9.5% | |
| 295/40R17 | 26.3" | 11.6" | 4.6" | −10.6% |
Sizes within 2% of 29.4" on 16" or 15" or 18" wheels.
| Size | Diameter | Width | Sidewall | vs 315/50R17 | |
|---|---|---|---|---|---|
| 285/60R16 | 29.5" | 11.2" | 6.7" | +0.2% | |
| 245/75R15 | 29.5" | 9.6" | 7.2" | +0.2% | |
| 265/55R18 | 29.5" | 10.4" | 5.7" | +0.3% | |
| 245/70R16 | 29.5" | 9.6" | 6.8" | +0.3% | |
| 225/75R16 | 29.3" | 8.9" | 6.6" | −0.4% | |
| 215/80R16 | 29.5" | 8.5" | 6.8" | +0.5% |
Actual speed when the speedometer is calibrated for 315/50R17.
| Speedometer shows | on 305/55R17 | on 325/45R17 | on 315/55R17 |
|---|---|---|---|
| 30 mph | 30.8 mph | 29.1 mph | 31.3 mph |
| 45 mph | 46.2 mph | 43.6 mph | 46.9 mph |
| 60 mph | 61.6 mph | 58.2 mph | 62.5 mph |
| 70 mph | 71.9 mph | 67.9 mph | 73.0 mph |
29.4 inches (747 mm). The sidewall is 6.2 inches.
12.4 inches (315 mm) section width, measured sidewall to sidewall.
About 29.4x12.4R17.
305/55R17 is +2.7% in diameter, within the common 3% guideline. It is 0.4" narrower.