285/65R18
Overall diameter
32.59″
828 mm
Sidewall height
7.29″
185.3 mm
Tread width
285 mm
11.2″
Circumference
102.37″
8.5 ft
Revs per mile
619
385 per km
Wheel diameter
18″
aspect ratio 65%
Cross-section
- Overall diameter
- 32.59″
- Sidewall (each side)
- 7.29″
- Wheel
- 18″
285/65R18 compared with other sizes
All 35 practical swaps involving 285/65R18 — diameter change, speedometer impact and a fit verdict for each.
285/65R18 → 285/75R16
285/75R16
Diameter −0.7% · Good fit
285/65R18 → 255/75R17
255/75R17
Diameter +1.6% · Good fit
285/65R18 → 285/70R17
285/70R17
Diameter −0.4% · Good fit
285/65R18 → 305/65R17
305/65R17
Diameter −0.1% · Good fit
285/65R18 → 305/70R17
305/70R17
Diameter −3.6% · Marginal fit — proceed with care
285/65R18 → 315/70R17
315/70R17
Diameter −5.2% · Not recommended
285/65R18 → 255/65R18
255/65R18
Diameter +4.9% · Marginal fit — proceed with care
285/65R18 → 255/70R18
255/70R18
Diameter +1.7% · Good fit
285/65R18 → 265/65R18
265/65R18
Diameter +3.2% · Marginal fit — proceed with care
285/65R18 → 265/70R18
265/70R18
Diameter −0.1% · Good fit
285/65R18 → 275/60R18
275/60R18
Diameter +5.1% · Not recommended
285/65R18 → 275/65R18
275/65R18
Diameter +1.6% · Good fit
285/65R18 → 275/70R18
275/70R18
Diameter −1.7% · Good fit
285/65R18 → 285/60R18
285/60R18
Diameter +3.6% · Marginal fit — proceed with care
265/70R18 → 285/65R18
265/70R18
Diameter +0.1% · Good fit
305/60R18 → 285/65R18
305/60R18
Diameter −0.5% · Good fit
275/65R18 → 285/65R18
275/65R18
Diameter −1.6% · Good fit
255/70R18 → 285/65R18
255/70R18
Diameter −1.6% · Good fit
275/70R18 → 285/65R18
275/70R18
Diameter +1.8% · Good fit
285/60R18 → 285/65R18
285/60R18
Diameter −3.4% · Marginal fit — proceed with care
285/70R18 → 285/65R18
285/70R18
Diameter +3.4% · Marginal fit — proceed with care
265/65R18 → 285/65R18
265/65R18
Diameter −3.1% · Marginal fit — proceed with care
285/70R17 → 285/65R18
285/70R17
Diameter +0.4% · Good fit
285/75R16 → 285/65R18
285/75R16
Diameter +0.7% · Good fit
285/55R20 → 285/65R18
285/55R20
Diameter −0.7% · Good fit
255/65R18 → 285/65R18
255/65R18
Diameter −4.7% · Marginal fit — proceed with care
275/60R18 → 285/65R18
275/60R18
Diameter −4.9% · Marginal fit — proceed with care
305/65R17 → 285/65R18
305/65R17
Diameter +0.1% · Good fit
285/65R18 → 285/70R18
285/70R18
Diameter −3.3% · Marginal fit — proceed with care
285/65R18 → 295/70R18
295/70R18
Diameter −4.9% · Marginal fit — proceed with care
285/65R18 → 305/60R18
305/60R18
Diameter +0.5% · Good fit
285/65R18 → 265/60R20
265/60R20
Diameter +0.2% · Good fit
285/65R18 → 285/55R20
285/55R20
Diameter +0.8% · Good fit
285/65R18 → 285/60R20
285/60R20
Diameter −2.6% · Good fit
285/65R18 → 235/45R18
235/45R18
Diameter +23.8% · Not recommended
Common questions
- What is the overall diameter of a 285/65R18 tire?
- A 285/65R18 tire is about 32.59″ (828 mm) in overall diameter, with a sidewall height of 185.3 mm and a circumference of 102.37″.
- How many revolutions per mile does a 285/65R18 tire turn?
- A 285/65R18 turns roughly 619 revolutions per mile (385 per kilometre). This is the number that determines speedometer and odometer accuracy when you change tire size.
- What do the numbers in 285/65R18 mean?
- 285 is the tread width in millimetres, 65 is the aspect ratio — the sidewall height as a percentage of the tread width — and 18 is the wheel diameter in inches. So the sidewall is 285 × 65% = 185.3 mm tall.