34.6" tall, 11.2" wide, 7.3" sidewall
A 285/65R20 tire is 34.6 inches (879 mm) tall and 11.2 inches wide. The sidewall is 65% of the width, 7.3 inches, on a 20-inch wheel, and the tire turns about 583 times per mile.
In flotation terms that is about 34.6x11.2R20, closest to the common 35x11.50R20 (35.0"). People often call it a 35-inch tire.
The size most often compared with it is 275/65R20, which is 0.5" shorter (−1.5%). At an indicated 60 mph you would be doing 59.1 mph on it.
| Current | New | Difference |
|---|
| Shows | Actual speed |
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Same 20" wheel, within 20 mm of width and 10 points of aspect ratio.
| Size | Diameter | Width | Sidewall | vs 285/65R20 | |
|---|---|---|---|---|---|
| 265/70R20 | 34.6" | 10.4" | 7.3" | +0.1% | |
| 305/60R20 | 34.4" | 12.0" | 7.2" | −0.5% | |
| 35x11.50R20 | 35.0" | 11.5" | 7.5" | +1.2% | |
| 295/65R20 | 35.1" | 11.6" | 7.5" | +1.5% | compare |
| 275/65R20 | 34.1" | 10.8" | 7.0" | −1.5% | compare |
| 275/70R20 | 35.2" | 10.8" | 7.6" | +1.7% | |
| 295/60R20 | 33.9" | 11.6" | 7.0" | −1.9% | |
| 265/65R20 | 33.6" | 10.4" | 6.8" | −3.0% | |
| 305/65R20 | 35.6" | 12.0" | 7.8" | +3.0% | |
| 265/75R20 | 35.6" | 10.4" | 7.8" | +3.1% |
Sizes within 2% of 34.6" on 18" or 22" wheels.
| Size | Diameter | Width | Sidewall | vs 285/65R20 | |
|---|---|---|---|---|---|
| 325/65R18 | 34.6" | 12.8" | 8.3" | +0.1% | |
| 265/60R22 | 34.5" | 10.4" | 6.3" | −0.2% | |
| 265/80R18 | 34.7" | 10.4" | 8.3" | +0.3% | |
| 225/70R22 | 34.4" | 8.9" | 6.2" | −0.5% | |
| 315/50R22 | 34.4" | 12.4" | 6.2" | −0.5% | |
| 295/55R22 | 34.8" | 11.6" | 6.4" | +0.5% |
Actual speed when the speedometer is calibrated for 285/65R20.
| Speedometer shows | on 275/65R20 | on 295/65R20 | on 265/70R20 |
|---|---|---|---|
| 30 mph | 29.6 mph | 30.4 mph | 30.0 mph |
| 45 mph | 44.3 mph | 45.7 mph | 45.0 mph |
| 60 mph | 59.1 mph | 60.9 mph | 60.0 mph |
| 70 mph | 69.0 mph | 71.0 mph | 70.0 mph |
34.6 inches (879 mm). The sidewall is 7.3 inches.
11.2 inches (285 mm) section width, measured sidewall to sidewall.
About 34.6x11.2R20; the closest common flotation size is 35x11.50R20 at 35.0".
275/65R20 is −1.5% in diameter, within the common 3% guideline. It is 0.4" narrower.