Tire sizes
What size is a 37-inch tire?
These common sizes all measure between 36.5 and 37.5 inches tall, so they get called 37s. Pick one for its exact dimensions.
| Size | Height | Width | Wheel |
|---|---|---|---|
| 37x12.50R17 | 37.0 in | 12.5 in | 17 in |
| 37x13.50R17 | 37.0 in | 13.5 in | 17 in |
| 37x12.50R18 | 37.0 in | 12.5 in | 18 in |
| 37x12.50R20 | 37.0 in | 12.5 in | 20 in |
| 37x13.50R20 | 37.0 in | 13.5 in | 20 in |
Questions
What size is a 37-inch tire in metric?
Few common metric sizes measure 37 inches; inch-sized tires such as 37x12.50 are the usual choice.
Is a 37-inch tire exactly 37 inches tall?
Not always. '37s' is a class: metric sizes from about 36.5 to 37.5 inches get called 37s, and inch-sized tires often measure a little under their label once mounted.
What gear ratio do I need for 37-inch tires?
From a 31.5-inch stock tire, 3.73 gears need about 4.38 and 4.10 gears about 4.82 to drive the same on 37s, so 4.30 and 4.88 are the nearest common sets. Use the calculator with your exact sizes.
Nominal dimensions. Fitment depends on your vehicle, lift and wheels. Updated 2026-11-14.