33.5" tall, 11.2" wide, 6.7" sidewall
A 285/60R20 tire is 33.5 inches (850 mm) tall and 11.2 inches wide. The sidewall is 60% of the width, 6.7 inches, on a 20-inch wheel, and the tire turns about 603 times per mile.
In flotation terms that is about 33.5x11.2R20, closest to the common 33x12.50R20 (33.0"). People often call it a 33-inch tire.
The size most often compared with it is 275/60R20, which is 0.5" shorter (−1.4%). At an indicated 60 mph you would be doing 59.2 mph on it.
| Current | New | Difference |
|---|
| Shows | Actual speed |
|---|
Same 20" wheel, within 20 mm of width and 10 points of aspect ratio.
| Size | Diameter | Width | Sidewall | vs 285/60R20 | |
|---|---|---|---|---|---|
| 265/65R20 | 33.6" | 10.4" | 6.8" | +0.3% | |
| 305/55R20 | 33.2" | 12.0" | 6.6" | −0.8% | |
| 275/60R20 | 33.0" | 10.8" | 6.5" | −1.4% | compare |
| 295/60R20 | 33.9" | 11.6" | 7.0" | +1.4% | compare |
| 275/65R20 | 34.1" | 10.8" | 7.0" | +1.8% | compare |
| 295/55R20 | 32.8" | 11.6" | 6.4" | −2.1% | |
| 265/60R20 | 32.5" | 10.4" | 6.3" | −2.8% | |
| 305/60R20 | 34.4" | 12.0" | 7.2" | +2.8% | |
| 285/65R20 | 34.6" | 11.2" | 7.3" | +3.4% | |
| 285/55R20 | 32.3" | 11.2" | 6.2" | −3.4% |
Sizes within 2% of 33.5" on 19" or 22" or 18" wheels.
| Size | Diameter | Width | Sidewall | vs 285/60R20 | |
|---|---|---|---|---|---|
| 245/75R19 | 33.5" | 9.6" | 7.2" | +0.0% | |
| 325/45R22 | 33.5" | 12.8" | 5.8" | +0.2% | |
| 325/60R18 | 33.4" | 12.8" | 7.7" | −0.3% | |
| 265/70R19 | 33.6" | 10.4" | 7.3" | +0.4% | |
| 305/65R18 | 33.6" | 12.0" | 7.8" | +0.4% | |
| 295/50R22 | 33.6" | 11.6" | 5.8" | +0.4% |
Actual speed when the speedometer is calibrated for 285/60R20.
| Speedometer shows | on 275/60R20 | on 275/65R20 | on 33x12.50R20 |
|---|---|---|---|
| 30 mph | 29.6 mph | 30.5 mph | 29.6 mph |
| 45 mph | 44.4 mph | 45.8 mph | 44.4 mph |
| 60 mph | 59.2 mph | 61.1 mph | 59.2 mph |
| 70 mph | 69.0 mph | 71.3 mph | 69.0 mph |
33.5 inches (850 mm). The sidewall is 6.7 inches.
11.2 inches (285 mm) section width, measured sidewall to sidewall.
About 33.5x11.2R20; the closest common flotation size is 33x12.50R20 at 33.0".
275/60R20 is −1.4% in diameter, within the common 3% guideline. It is 0.4" narrower.