Home › 20" tire sizes › 285/55R20
285/55R20 tire size in inches
285/55R20 is 32.34" tall and 11.22" wide, and fits a 20" rim. In flotation (inch) sizing that is roughly 32.3x11.2R20.
285/55R20 dimensions
| Measurement | Inches | Metric |
|---|---|---|
| Overall diameter (height) | 32.34" | 822 mm |
| Section width | 11.22" | 285 mm |
| Sidewall height | 6.17" | 156.8 mm |
| Rim diameter | 20" | 508.0 mm |
| Circumference | 101.6" | 2581 mm |
| Revolutions per mile | 624 | |
| Aspect ratio | 55% (sidewall is 55% of the width) | |
Drawn to scale
Among the 131 sizes for 20" wheels on this site, 285/55R20 is #64 by height (shortest: 225/30R20, tallest: 365/85R20).
What people compare 285/55R20 with
Real comparisons drivers search for, worked out against 285/55R20:
| Compared size | Height | Width | Sidewall | Speedo at true 60 |
|---|---|---|---|---|
| 275/60R20 | +0.65" (+2.01%) | -0.39" | +0.33" | 58.8 mph |
| 275/55R20 | -0.43" (-1.33%) | -0.39" | -0.22" | 60.8 mph |
| 295/55R20 | +0.44" (+1.36%) | +0.39" | +0.22" | 59.2 mph |
| 285/60R20 | +1.12" (+3.46%) | 0.00" | +0.56" | 58 mph |
| 275/65R20 | +1.73" (+5.35%) | -0.39" | +0.87" | 57 mph |
| 305/55R20 | +0.87" (+2.69%) | +0.79" | +0.43" | 58.4 mph |
| 285/65R20 | +2.25" (+6.96%) | 0.00" | +1.12" | 56.1 mph |
| 265/60R20 | +0.18" (+0.56%) | -0.79" | +0.09" | 59.7 mph |
How the 285/55R20 numbers are worked out
The size code reads as 285 mm section width, 55% aspect ratio, R for radial construction and 20-inch wheel.
- Sidewall = 285 × 55% = 156.8 mm = 6.17"
- Diameter = 20" + 2 × 6.17" = 32.34"
- Circumference = π × 32.34" = 101.6"
- Revs per mile = 63,360" ÷ 101.6" = 624
Sizes that can replace 285/55R20 on a 20" wheel
Within 3% of 32.34". Last column: speedometer reading at a true 60 mph.
| Size | Diameter | Width | Difference | Speedo at true 60 mph |
|---|---|---|---|---|
| 315/50R20 | 32.40" | 12.40" | +0.19% | 59.9 mph |
| 260/60R20 | 32.28" | 10.24" | -0.19% | 60.1 mph |
| 265/60R20 | 32.52" | 10.43" | +0.56% | 59.7 mph |
| 245/65R20 | 32.54" | 9.65" | +0.62% | 59.6 mph |
| 320/50R20 | 32.60" | 12.60" | +0.8% | 59.5 mph |
| 255/60R20 | 32.05" | 10.04" | -0.9% | 60.5 mph |
| 235/65R20 | 32.03" | 9.25" | -0.96% | 60.6 mph |
| 305/50R20 | 32.01" | 12.01" | -1.02% | 60.6 mph |
| 270/60R20 | 32.76" | 10.63" | +1.3% | 59.2 mph |
| 275/55R20 | 31.91" | 10.83" | -1.33% | 60.8 mph |
| 295/55R20 | 32.78" | 11.61" | +1.36% | 59.2 mph |
| 325/50R20 | 32.80" | 12.80" | +1.42% | 59.2 mph |
One size wider or narrower
Same height on a different wheel size
- 315/70R15 15" (+0.06%)
- 295/75R15 15" (+0.25%)
- 255/85R15 15" (-0.83%)
- 265/85R15 15" (+1.24%)
- 285/75R15 15" (-1.58%)
- 305/70R15 15" (-1.64%)
- 245/85R16 16" (+0.19%)
- 295/70R16 16" (-0.25%)
- 275/75R16 16" (-0.31%)
- 375/55R16 16" (-0.31%)
Questions about 285/55R20
How tall is a 285/55R20 tire in inches?
A 285/55R20 tire is 32.34 inches (822 mm) tall: the 20-inch rim plus two sidewalls of 6.17 inches each.
Is 285/55R20 a 32 inch tire?
Yes. At 32.34 inches tall it is commonly called a 32-inch tire.
How many revolutions per mile does a 285/55R20 make?
About 624 revolutions per mile, based on a calculated circumference of 101.6 inches.
What size can replace 285/55R20?
315/50R20 is the closest match on a 20" rim (+0.19% height). Check load index, speed rating and clearance first.
Compare 285/55R20 against any other size with the tire size calculator.