245/50R20 — a 20-inch wheel doing a crossover's job
The point at which a 20-inch wheel stops being a performance choice and becomes a trim level.
Metric notation · Crossover and SUV
- Overall diameter
- 29.65 in
- 753 mm
- Section width
- 9.65 in
- 245 mm
- Sidewall height
- 4.82 in
- 123 mm
- Aspect ratio
- 50%
- sidewall as a share of width
- Wheel diameter
- 20 in
- the hole in the middle
- Circumference
- 93.1 in
- 2366 mm
- Revolutions per mile
- 680.3
- geometric, not measured
- Revolutions per km
- 422.7
- geometric, not measured
- Typical load index
- 98–116
- 1653–2756 lb per tire
Crossovers are heavier than the cars they share size families with, so the same nominal size is produced at a higher index for SUV fitment than for passenger fitment. Two tires wearing the same size code can carry materially different loads.
The load-index range shown is the band this CLASS of size is typically produced in — not a list of what is in stock for this exact size today. Load index and speed symbol are printed on the sidewall of the specific tire you are holding, and the required minimum is on the placard of the specific vehicle you are fitting. Read both.
Nearest real sizes in imperial notation, same wheel
- 33x12.50R2033.00 in tall+3.35 in
- 35x12.50R2035.00 in tall+5.35 in
- 37x12.50R2037.00 in tall+7.35 in
Compare any two sizes, including ones this site has no page for, in the comparison tool.
Mid-size and full-size crossovers in their upper trims use this size — the wheel is large for appearance rather than for brake clearance, and the tire is sized to keep the vehicle's rolling diameter where the drivetrain expects it.
The crossover stack at 245 mm
| Size | Wheel | Diameter | Sidewall |
|---|---|---|---|
| 245/65R17 | 17 in | 29.54 in | 6.27 in |
| 245/60R18 | 18 in | 29.57 in | 5.79 in |
| 245/50R20 | 20 in | 29.65 in | 4.82 in |
Three wheel diameters, 0.11 in of total variation, and sidewalls running from 6.27 in down to 4.82 in. The 17 and 18-inch entries are 0.12% apart; this size is 0.36% above the 17.
The gap between the 18 and the 20 is two wheel sizes rather than one, which is why the aspect ratio drops ten points rather than five between them. There is no 245/55R19 in this catalogue to fill it.
What 4.82 inches of sidewall means on a 20
It is a great deal more than the 3.38 in that 245/35R20 carries on the same wheel and the same section width — nearly an inch and a half more casing. The two sizes differ by 2.89 in of diameter as a result, which measured from the smaller is 10.82%.
A 20-inch wheel, in other words, tells you nothing about whether the tire on it is a low-profile one.
Around this diameter
225/75R16 sits 0.36 in below at 29.29 in, from the light-truck part of the catalogue. 235/65R18 and 255/60R18 sit 0.38 in and 0.40 in above at 30.03 in and 30.05 in. 30x9.50R15 lands 0.35 in above at 30.00 in — a flotation size on a 15-inch wheel, matching a 20-inch crossover fitment to within a third of an inch.
What a 20-inch wheel costs elsewhere
Nothing in the arithmetic changes when a vehicle moves from the 17-inch package to this one, but two things outside it do. The wheel is heavier at a larger radius, and the tire has 1.45 in less casing at each end to absorb what the road does. Neither shows up in a diameter, a circumference or a revolutions-per-mile figure, and neither is a defect — they are the price of the appearance the larger wheel was chosen for.
Where the wheel itself is being changed rather than just the tire, offset and backspacing decide whether the assembly clears anything; the wheel offset and backspacing reference covers those.
Related
- 33x12.50R2033.00 in tall
- 35x12.50R2035.00 in tall
- 37x12.50R2037.00 in tall
Class: Crossover and SUV. Every figure above is computed from the size code, not stored — see how these numbers are calculated.