305/50R20
A 305/50R20 tire is 32.01 inches tall and 12.0 inches wide, with a 6.00-inch sidewall, mounted on a 20-inch wheel.
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 in inches and millimeters
Every dimension of a 305/50R20, converted both ways. Calculated from the size code, accurate to about 1%.
| Measurement | Inches | Millimeters |
|---|---|---|
| Overall diameter (height) | 32.01″ | 813 mm |
| Tread width | 12.0″ | 305 mm |
| Sidewall height | 6.00″ | 152.5 mm |
| Wheel diameter | 20″ | 508 mm |
| Circumference | 100.56″ | 2554 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.
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% · This fits
305/50R20 → 305/60R18
305/60R18
Diameter −1.2% · This fits
305/50R20 → 265/50R20
265/50R20
Diameter +5.2% · Too big a jump
305/50R20 → 265/55R20
265/55R20
Diameter +1.7% · This fits
305/50R20 → 265/60R20
265/60R20
Diameter −1.6% · This fits
305/50R20 → 275/60R20
275/60R20
Diameter −3.0% · This fits
305/50R20 → 285/50R20
285/50R20
Diameter +2.5% · This fits
305/50R20 → 285/55R20
285/55R20
Diameter −1.0% · This fits
305/50R20 → 285/60R20
285/60R20
Diameter −4.4% · Borderline. Check clearance first
275/55R20 → 305/50R20
275/55R20
Diameter −0.3% · This fits
285/55R20 → 305/50R20
285/55R20
Diameter +1.0% · This fits
265/60R20 → 305/50R20
265/60R20
Diameter +1.6% · This fits
265/55R20 → 305/50R20
265/55R20
Diameter −1.7% · This fits
285/50R20 → 305/50R20
285/50R20
Diameter −2.5% · This fits
305/55R20 → 305/50R20
305/55R20
Diameter +3.8% · Borderline. Check clearance first
275/60R20 → 305/50R20
275/60R20
Diameter +3.1% · Borderline. Check clearance first
285/60R20 → 305/50R20
285/60R20
Diameter +4.6% · Borderline. Check clearance first
265/50R20 → 305/50R20
265/50R20
Diameter −4.9% · Borderline. Check clearance first
305/60R18 → 305/50R20
305/60R18
Diameter +1.3% · This fits
275/65R18 → 305/50R20
275/65R18
Diameter +0.2% · This fits
285/45R22 → 305/50R20
285/45R22
Diameter +0.3% · This fits
275/50R21 → 305/50R20
275/50R21
Diameter −0.6% · This fits
305/45R22 → 305/50R20
305/45R22
Diameter +2.5% · This fits
305/50R20 → 305/55R20
305/55R20
Diameter −3.6% · Borderline. Check clearance first
305/50R20 → 275/50R21
275/50R21
Diameter +0.6% · This fits
305/50R20 → 275/50R22
275/50R22
Diameter −2.5% · This fits
305/50R20 → 285/45R22
285/45R22
Diameter −0.3% · This fits
305/50R20 → 285/50R22
285/50R22
Diameter −3.7% · Borderline. Check clearance first
305/50R20 → 305/45R22
305/45R22
Diameter −2.4% · This fits
Common questions
- What is 305/50R20 in inches?
- A 305/50R20 tire is 32.01 inches tall and 12.0 inches wide, with a 6.00-inch sidewall, mounted on a 20-inch wheel. In metric that is 813 mm tall and 305 mm wide. The circumference is 100.56 inches.
- How tall is a 305/50R20 tire?
- 32.01 inches, or 813 mm. That is the overall diameter, wheel included. It turns about 630 times per mile, which is what your speedometer counts.
- What do the numbers in 305/50R20 mean?
- 305 is the tread width in millimeters, 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.