305/70R17
Overall diameter
33.81″
859 mm
Sidewall height
8.41″
213.5 mm
Tread width
305 mm
12.0″
Circumference
106.22″
8.9 ft
Revs per mile
596
371 per km
Wheel diameter
17″
aspect ratio 70%
Cross-section
- Overall diameter
- 33.81″
- Sidewall (each side)
- 8.41″
- Wheel
- 17″
305/70R17 compared with other sizes
All 20 practical swaps involving 305/70R17 — diameter change, speedometer impact and a fit verdict for each.
305/70R17 → 285/75R16
285/75R16
Diameter +3.0% · Good fit
305/70R17 → 275/70R17
275/70R17
Diameter +5.1% · Not recommended
305/70R17 → 285/70R17
285/70R17
Diameter +3.4% · Marginal fit — proceed with care
305/70R17 → 305/65R17
305/65R17
Diameter +3.7% · Marginal fit — proceed with care
315/70R17 → 305/70R17
315/70R17
Diameter +1.6% · Good fit
305/65R17 → 305/70R17
305/65R17
Diameter −3.6% · Marginal fit — proceed with care
285/70R17 → 305/70R17
285/70R17
Diameter −3.3% · Marginal fit — proceed with care
275/70R17 → 305/70R17
275/70R17
Diameter −4.9% · Marginal fit — proceed with care
285/70R18 → 305/70R17
285/70R18
Diameter −0.3% · Good fit
295/70R18 → 305/70R17
295/70R18
Diameter +1.3% · Good fit
275/70R18 → 305/70R17
275/70R18
Diameter −1.9% · Good fit
305/60R18 → 305/70R17
305/60R18
Diameter −4.1% · Marginal fit — proceed with care
285/75R16 → 305/70R17
285/75R16
Diameter −2.9% · Good fit
265/70R18 → 305/70R17
265/70R18
Diameter −3.6% · Marginal fit — proceed with care
285/65R18 → 305/70R17
285/65R18
Diameter −3.6% · Marginal fit — proceed with care
275/65R18 → 305/70R17
275/65R18
Diameter −5.1% · Not recommended
305/70R17 → 315/70R17
315/70R17
Diameter −1.6% · Good fit
305/70R17 → 285/70R18
285/70R18
Diameter +0.3% · Good fit
305/70R17 → 295/70R18
295/70R18
Diameter −1.3% · Good fit
305/70R17 → 225/45R17
225/45R17
Diameter +35.4% · Not recommended
Common questions
- What is the overall diameter of a 305/70R17 tire?
- A 305/70R17 tire is about 33.81″ (859 mm) in overall diameter, with a sidewall height of 213.5 mm and a circumference of 106.22″.
- How many revolutions per mile does a 305/70R17 tire turn?
- A 305/70R17 turns roughly 596 revolutions per mile (371 per kilometre). This is the number that determines speedometer and odometer accuracy when you change tire size.
- What do the numbers in 305/70R17 mean?
- 305 is the tread width in millimetres, 70 is the aspect ratio — the sidewall height as a percentage of the tread width — and 17 is the wheel diameter in inches. So the sidewall is 305 × 70% = 213.5 mm tall.