285/55R20
A 285/55R20 tire is 32.34 inches tall and 11.2 inches wide, with a 6.17-inch sidewall, mounted on a 20-inch wheel.
Overall diameter
32.34″
822 mm
Sidewall height
6.17″
156.8 mm
Tread width
285 mm
11.2″
Circumference
101.61″
8.5 ft
Revs per mile
624
387 per km
Wheel diameter
20″
aspect ratio 55%
Cross-section
- Overall diameter
- 32.34″
- Sidewall (each side)
- 6.17″
- Wheel
- 20″
285/55R20 in inches and millimeters
Every dimension of a 285/55R20, converted both ways. Calculated from the size code, accurate to about 1%.
| Measurement | Inches | Millimeters |
|---|---|---|
| Overall diameter (height) | 32.34″ | 822 mm |
| Tread width | 11.2″ | 285 mm |
| Sidewall height | 6.17″ | 156.8 mm |
| Wheel diameter | 20″ | 508 mm |
| Circumference | 101.61″ | 2581 mm |
Nominal dimensions from the size code. A real tire varies by a few millimeters between manufacturers, and a loaded tire sits slightly shorter than its free diameter.
285/55R20 compared with other sizes
All 33 practical swaps involving 285/55R20 — diameter change, speedometer impact and a fit verdict for each.
285/55R20 → 275/55R20
275/55R20
Diameter +1.4% · This fits
285/55R20 → 285/65R18
285/65R18
Diameter −0.7% · This fits
285/55R20 → 305/60R18
305/60R18
Diameter −0.2% · This fits
285/55R20 → 255/55R20
255/55R20
Diameter +4.2% · Borderline. Check clearance first
285/55R20 → 265/55R20
265/55R20
Diameter +2.8% · This fits
285/55R20 → 265/60R20
265/60R20
Diameter −0.5% · This fits
285/55R20 → 275/60R20
275/60R20
Diameter −2.0% · This fits
285/55R20 → 275/65R20
275/65R20
Diameter −5.1% · Too big a jump
285/55R20 → 285/50R20
285/50R20
Diameter +3.6% · Borderline. Check clearance first
265/60R20 → 285/55R20
265/60R20
Diameter +0.5% · This fits
305/50R20 → 285/55R20
305/50R20
Diameter −1.0% · This fits
275/55R20 → 285/55R20
275/55R20
Diameter −1.3% · This fits
275/60R20 → 285/55R20
275/60R20
Diameter +2.0% · This fits
285/50R20 → 285/55R20
285/50R20
Diameter −3.5% · Borderline. Check clearance first
285/60R20 → 285/55R20
285/60R20
Diameter +3.5% · Borderline. Check clearance first
265/55R20 → 285/55R20
265/55R20
Diameter −2.7% · This fits
305/55R20 → 285/55R20
305/55R20
Diameter +2.7% · This fits
255/55R20 → 285/55R20
255/55R20
Diameter −4.0% · Borderline. Check clearance first
285/65R18 → 285/55R20
285/65R18
Diameter +0.8% · This fits
285/45R22 → 285/55R20
285/45R22
Diameter −0.8% · This fits
295/60R20 → 285/55R20
295/60R20
Diameter +4.9% · Borderline. Check clearance first
305/60R18 → 285/55R20
305/60R18
Diameter +0.2% · This fits
275/65R20 → 285/55R20
275/65R20
Diameter +5.4% · Too big a jump
285/55R20 → 285/60R20
285/60R20
Diameter −3.4% · Borderline. Check clearance first
285/55R20 → 295/60R20
295/60R20
Diameter −4.7% · Borderline. Check clearance first
285/55R20 → 305/50R20
305/50R20
Diameter +1.0% · This fits
285/55R20 → 305/55R20
305/55R20
Diameter −2.6% · This fits
285/55R20 → 275/50R21
275/50R21
Diameter +1.6% · This fits
285/55R20 → 275/50R22
275/50R22
Diameter −1.5% · This fits
285/55R20 → 285/40R22
285/40R22
Diameter +4.4% · Borderline. Check clearance first
285/55R20 → 285/45R22
285/45R22
Diameter +0.8% · This fits
285/55R20 → 285/50R22
285/50R22
Diameter −2.6% · This fits
285/55R20 → 305/45R22
305/45R22
Diameter −1.4% · This fits
Common questions
- What is 285/55R20 in inches?
- A 285/55R20 tire is 32.34 inches tall and 11.2 inches wide, with a 6.17-inch sidewall, mounted on a 20-inch wheel. In metric that is 822 mm tall and 285 mm wide. The circumference is 101.61 inches.
- How tall is a 285/55R20 tire?
- 32.34 inches, or 822 mm. That is the overall diameter, wheel included. It turns about 624 times per mile, which is what your speedometer counts.
- What do the numbers in 285/55R20 mean?
- 285 is the tread width in millimeters, 55 is the aspect ratio — the sidewall height as a percentage of the tread width — and 20 is the wheel diameter in inches. So the sidewall is 285 × 55% = 156.8 mm tall.