Tire size
37x12.50R18 in metric
A 37x12.50R18 tire is 37.0 inches (940 mm) tall and 12.5 inches (318 mm) wide, on a 18-inch wheel. Its sidewall is 76% of its width.
| 37x12.50R18 | Inches | Metric |
|---|---|---|
| Overall diameter (height) | 37.0 in | 940 mm |
| Section width | 12.5 in | 318 mm |
| Sidewall height | 9.5 in | 241 mm |
| Wheel (rim) diameter | 18 in | 457 mm |
| Circumference | 116.2 in | 2952 mm |
| Revolutions | 545 per mile | 339 per km |
How it's worked out
Inch sizes give the height first: 37x12.50R18 is 37.0 in tall and 12.5 in wide for a 18 in wheel, so each sidewall is (37.0 - 18) / 2 = 9.5 in.
Similar sizes
Sizes within about 3.5% of the height of 37x12.50R18. The last column is your real speed at an indicated 60 mph if your speedometer was set for 37x12.50R18.
| Size | Height | vs 37x12.50R18 | Real speed at 60 mph shown |
|---|---|---|---|
| 37x12.50R17 | 37.0 in | +0.0% | 60.0 mph |
| 37x12.50R20 | 37.0 in | +0.0% | 60.0 mph |
| 37x13.50R17 | 37.0 in | +0.0% | 60.0 mph |
| 37x13.50R20 | 37.0 in | +0.0% | 60.0 mph |
Questions
What is 37x12.50R18 in metric?
940 mm tall and 318 mm wide on a 18-inch wheel.
How tall is a 37x12.50R18 tire?
37.0 inches on paper. Many inch-sized tires measure slightly under their label once mounted, so check the maker's spec sheet if it matters.
How many revolutions per mile does 37x12.50R18 do?
About 545 per mile (339 per km).
Nominal dimensions, calculated from the size marking. Real tires differ slightly by brand, rim width, pressure and wear. Fitment depends on your vehicle, lift and wheels: this page doesn't say whether a size fits. Updated 2026-11-14.