38.5x14.50R15 tire size
38.5x14.50R15 is a flotation (inch) size: 38.5" tall, 14.5" wide, on a 15" rim — about a 370/80R15. The sidewall is 11.8" and the tire turns 524 times per mile.
38.5x14.50R15 specs
| Overall diameter (height) | 38.50" · 978 mm |
|---|---|
| Section width | 14.50" · 368 mm |
| Sidewall height | 11.75" · 298 mm (81% of width) |
| Rim diameter | 15" |
| Circumference | 120.95" · 3.072 m |
| Revolutions per mile | 524 (326 per km) |
| Closest metric size | 370/80R15 |
Equivalent sizes on a 15" rim
Sizes within ±5% of the overall diameter. Green rows are inside the usual ±3% limit for keeping the speedometer, ABS and gearing right; red rows are bigger changes that need clearance checks.
| Size | Diameter | Difference | Width | Speedo at 60 | |
|---|---|---|---|---|---|
| 37x12.50R15 | 37.00" | -3.90% | -50 mm | 57.7 mph | calculate → |
| 38x15.50R15 | 38.00" | -1.30% | +26 mm | 59.2 mph | calculate → |
| 38x12.50R15 | 38.00" | -1.30% | -50 mm | 59.2 mph | calculate → |
| 39.5x13.50R15 | 39.50" | +2.60% | -25 mm | 61.6 mph | calculate → |
| 37x14.50R15 | 37.00" | -3.90% | 0 mm | 57.7 mph | calculate → |
| 38.5x11.00R15 | 38.50" | 0.00% | -89 mm | 60.0 mph | calculate → |
| 38.5x13.50R15 | 38.50" | 0.00% | -25 mm | 60.0 mph | calculate → |
| 38.5x15.00R15 | 38.50" | 0.00% | +13 mm | 60.0 mph | calculate → |
| 38.5x16.00R15 | 38.50" | 0.00% | +38 mm | 60.0 mph | calculate → |
| 38x13.00R15 | 38.00" | -1.30% | -38 mm | 59.2 mph | calculate → |
| 39.5x15.00R15 | 39.50" | +2.60% | +13 mm | 61.6 mph | calculate → |
| 39.5x18.00R15 | 39.50" | +2.60% | +89 mm | 61.6 mph | calculate → |
| 37x13.50R15 | 37.00" | -3.90% | -25 mm | 57.7 mph | calculate → |
| 37x13.00R15 | 37.00" | -3.90% | -38 mm | 57.7 mph | calculate → |
| 37x14.00R15 | 37.00" | -3.90% | -12 mm | 57.7 mph | calculate → |
| 40x16.00R15 | 40.00" | +3.90% | +38 mm | 62.3 mph | calculate → |
| 38x14.50R15 | 38.00" | -1.30% | 0 mm | 59.2 mph | calculate → |
| 39x13.50R15 | 39.00" | +1.30% | -25 mm | 60.8 mph | calculate → |
Plus / minus sizing: 14" and 16" rims
Same overall height on a different rim. Check wheel width and clearance before switching.
| Size | Diameter | Difference | Width | Speedo at 60 | |
|---|---|---|---|---|---|
| 38.5x14.50R16 | 38.50" | 0.00% | 0 mm | 60.0 mph | calculate → |
| 38.5x11.00R16 | 38.50" | 0.00% | -89 mm | 60.0 mph | calculate → |
| 38.5x13.50R16 | 38.50" | 0.00% | -25 mm | 60.0 mph | calculate → |
| 38.5x15.00R16 | 38.50" | 0.00% | +13 mm | 60.0 mph | calculate → |
Try another size against 38.5x14.50R15
Questions
What size is 38.5x14.50R15 in inches?
38.5x14.50R15 is about 38.5" tall and 14.5" wide on a 15-inch rim — roughly a 370/80R15 in inch sizing.
What does 38.5x14.50R15 mean?
38.5" overall diameter, 14.50" section width, radial, 15" rim.
What tire sizes are equivalent to 38.5x14.50R15?
On the same 15" rim, within 3% of the diameter: 38.5x11.00R15 (0.00%), 38.5x13.50R15 (0.00%), 38.5x15.00R15 (0.00%), 38.5x16.00R15 (0.00%), 38x12.50R15 (-1.30%), 38x13.00R15 (-1.30%).
How many revolutions per mile does a 38.5x14.50R15 tire make?
About 524 revolutions per mile (circumference 121.0").
How these numbers are computed
Diameter = rim + 2 × sidewall, sidewall = width × aspect ÷ 100, circumference = π × diameter, revolutions per mile = 63,360 ÷ circumference. Real tires differ by brand by a few tenths of an inch. Last reviewed October 14, 2026.