285/55R20
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 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% · Good fit
285/55R20 → 285/65R18
285/65R18
Diameter −0.7% · Good fit
285/55R20 → 305/60R18
305/60R18
Diameter −0.2% · Good fit
285/55R20 → 255/55R20
255/55R20
Diameter +4.2% · Marginal fit — proceed with care
285/55R20 → 265/55R20
265/55R20
Diameter +2.8% · Good fit
285/55R20 → 265/60R20
265/60R20
Diameter −0.5% · Good fit
285/55R20 → 275/60R20
275/60R20
Diameter −2.0% · Good fit
285/55R20 → 275/65R20
275/65R20
Diameter −5.1% · Not recommended
285/55R20 → 285/50R20
285/50R20
Diameter +3.6% · Marginal fit — proceed with care
265/60R20 → 285/55R20
265/60R20
Diameter +0.5% · Good fit
305/50R20 → 285/55R20
305/50R20
Diameter −1.0% · Good fit
275/55R20 → 285/55R20
275/55R20
Diameter −1.3% · Good fit
275/60R20 → 285/55R20
275/60R20
Diameter +2.0% · Good fit
285/50R20 → 285/55R20
285/50R20
Diameter −3.5% · Marginal fit — proceed with care
285/60R20 → 285/55R20
285/60R20
Diameter +3.5% · Marginal fit — proceed with care
265/55R20 → 285/55R20
265/55R20
Diameter −2.7% · Good fit
305/55R20 → 285/55R20
305/55R20
Diameter +2.7% · Good fit
255/55R20 → 285/55R20
255/55R20
Diameter −4.0% · Marginal fit — proceed with care
285/65R18 → 285/55R20
285/65R18
Diameter +0.8% · Good fit
285/45R22 → 285/55R20
285/45R22
Diameter −0.8% · Good fit
295/60R20 → 285/55R20
295/60R20
Diameter +4.9% · Marginal fit — proceed with care
305/60R18 → 285/55R20
305/60R18
Diameter +0.2% · Good fit
275/65R20 → 285/55R20
275/65R20
Diameter +5.4% · Not recommended
285/55R20 → 285/60R20
285/60R20
Diameter −3.4% · Marginal fit — proceed with care
285/55R20 → 295/60R20
295/60R20
Diameter −4.7% · Marginal fit — proceed with care
285/55R20 → 305/50R20
305/50R20
Diameter +1.0% · Good fit
285/55R20 → 305/55R20
305/55R20
Diameter −2.6% · Good fit
285/55R20 → 275/50R21
275/50R21
Diameter +1.6% · Good fit
285/55R20 → 275/50R22
275/50R22
Diameter −1.5% · Good fit
285/55R20 → 285/40R22
285/40R22
Diameter +4.4% · Marginal fit — proceed with care
285/55R20 → 285/45R22
285/45R22
Diameter +0.8% · Good fit
285/55R20 → 285/50R22
285/50R22
Diameter −2.6% · Good fit
285/55R20 → 305/45R22
305/45R22
Diameter −1.4% · Good fit
Common questions
- What is the overall diameter of a 285/55R20 tire?
- A 285/55R20 tire is about 32.34″ (822 mm) in overall diameter, with a sidewall height of 156.8 mm and a circumference of 101.61″.
- How many revolutions per mile does a 285/55R20 tire turn?
- A 285/55R20 turns roughly 624 revolutions per mile (387 per kilometre). This is the number that determines speedometer and odometer accuracy when you change tire size.
- What do the numbers in 285/55R20 mean?
- 285 is the tread width in millimetres, 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.