305/50R20
Overall diameter
32.01″
813 mm
Sidewall height
6.00″
152.5 mm
Tread width
305 mm
12.0″
Circumference
100.56″
8.4 ft
Revs per mile
630
392 per km
Wheel diameter
20″
aspect ratio 50%
Cross-section
- Overall diameter
- 32.01″
- Sidewall (each side)
- 6.00″
- Wheel
- 20″
305/50R20 compared with other sizes
All 29 practical swaps involving 305/50R20 — diameter change, speedometer impact and a fit verdict for each.
305/50R20 → 275/55R20
275/55R20
Diameter +0.3% · Good fit
305/50R20 → 305/60R18
305/60R18
Diameter −1.2% · Good fit
305/50R20 → 265/50R20
265/50R20
Diameter +5.2% · Not recommended
305/50R20 → 265/55R20
265/55R20
Diameter +1.7% · Good fit
305/50R20 → 265/60R20
265/60R20
Diameter −1.6% · Good fit
305/50R20 → 275/60R20
275/60R20
Diameter −3.0% · Good fit
305/50R20 → 285/50R20
285/50R20
Diameter +2.5% · Good fit
305/50R20 → 285/55R20
285/55R20
Diameter −1.0% · Good fit
305/50R20 → 285/60R20
285/60R20
Diameter −4.4% · Marginal fit — proceed with care
275/55R20 → 305/50R20
275/55R20
Diameter −0.3% · Good fit
285/55R20 → 305/50R20
285/55R20
Diameter +1.0% · Good fit
265/60R20 → 305/50R20
265/60R20
Diameter +1.6% · Good fit
265/55R20 → 305/50R20
265/55R20
Diameter −1.7% · Good fit
285/50R20 → 305/50R20
285/50R20
Diameter −2.5% · Good fit
305/55R20 → 305/50R20
305/55R20
Diameter +3.8% · Marginal fit — proceed with care
275/60R20 → 305/50R20
275/60R20
Diameter +3.1% · Marginal fit — proceed with care
285/60R20 → 305/50R20
285/60R20
Diameter +4.6% · Marginal fit — proceed with care
265/50R20 → 305/50R20
265/50R20
Diameter −4.9% · Marginal fit — proceed with care
305/60R18 → 305/50R20
305/60R18
Diameter +1.3% · Good fit
275/65R18 → 305/50R20
275/65R18
Diameter +0.2% · Good fit
285/45R22 → 305/50R20
285/45R22
Diameter +0.3% · Good fit
275/50R21 → 305/50R20
275/50R21
Diameter −0.6% · Good fit
305/45R22 → 305/50R20
305/45R22
Diameter +2.5% · Good fit
305/50R20 → 305/55R20
305/55R20
Diameter −3.6% · Marginal fit — proceed with care
305/50R20 → 275/50R21
275/50R21
Diameter +0.6% · Good fit
305/50R20 → 275/50R22
275/50R22
Diameter −2.5% · Good fit
305/50R20 → 285/45R22
285/45R22
Diameter −0.3% · Good fit
305/50R20 → 285/50R22
285/50R22
Diameter −3.7% · Marginal fit — proceed with care
305/50R20 → 305/45R22
305/45R22
Diameter −2.4% · Good fit
Common questions
- What is the overall diameter of a 305/50R20 tire?
- A 305/50R20 tire is about 32.01″ (813 mm) in overall diameter, with a sidewall height of 152.5 mm and a circumference of 100.56″.
- How many revolutions per mile does a 305/50R20 tire turn?
- A 305/50R20 turns roughly 630 revolutions per mile (392 per kilometre). This is the number that determines speedometer and odometer accuracy when you change tire size.
- What do the numbers in 305/50R20 mean?
- 305 is the tread width in millimetres, 50 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 305 × 50% = 152.5 mm tall.