255/50R20
A 255/50R20 tire is 30.04 inches tall and 10.0 inches wide, with a 5.02-inch sidewall, mounted on a 20-inch wheel.
Common fitments: Grand Cherokee, Durango
Overall diameter
30.04″
763 mm
Sidewall height
5.02″
127.5 mm
Tread width
255 mm
10.0″
Circumference
94.37″
7.9 ft
Revs per mile
671
417 per km
Wheel diameter
20″
aspect ratio 50%
Cross-section
- Overall diameter
- 30.04″
- Sidewall (each side)
- 5.02″
- Wheel
- 20″
255/50R20 in inches and millimeters
Every dimension of a 255/50R20, converted both ways. Calculated from the size code, accurate to about 1%.
| Measurement | Inches | Millimeters |
|---|---|---|
| Overall diameter (height) | 30.04″ | 763 mm |
| Tread width | 10.0″ | 255 mm |
| Sidewall height | 5.02″ | 127.5 mm |
| Wheel diameter | 20″ | 508 mm |
| Circumference | 94.37″ | 2397 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.
255/50R20 compared with other sizes
All 32 practical swaps involving 255/50R20 — diameter change, speedometer impact and a fit verdict for each.
255/50R20 → 255/45R20
255/45R20
Diameter +3.5% · Borderline. Check clearance first
255/50R20 → 275/45R20
275/45R20
Diameter +1.0% · This fits
255/50R20 → 235/65R18
235/65R18
Diameter +0.0% · This fits
255/50R20 → 255/60R18
255/60R18
Diameter −0.0% · This fits
255/50R20 → 245/45R20
245/45R20
Diameter +4.7% · Borderline. Check clearance first
255/50R20 → 245/50R20
245/50R20
Diameter +1.3% · This fits
275/45R20 → 255/50R20
275/45R20
Diameter −1.0% · This fits
245/50R20 → 255/50R20
245/50R20
Diameter −1.3% · This fits
265/50R20 → 255/50R20
265/50R20
Diameter +1.3% · This fits
255/45R20 → 255/50R20
255/45R20
Diameter −3.3% · Borderline. Check clearance first
255/55R20 → 255/50R20
255/55R20
Diameter +3.3% · Borderline. Check clearance first
265/45R20 → 255/50R20
265/45R20
Diameter −2.2% · This fits
255/60R18 → 255/50R20
255/60R18
Diameter +0.0% · This fits
285/50R20 → 255/50R20
285/50R20
Diameter +3.9% · Borderline. Check clearance first
245/45R20 → 255/50R20
245/45R20
Diameter −4.5% · Borderline. Check clearance first
275/40R20 → 255/50R20
275/40R20
Diameter −4.6% · Borderline. Check clearance first
265/55R20 → 255/50R20
265/55R20
Diameter +4.8% · Borderline. Check clearance first
235/65R18 → 255/50R20
235/65R18
Diameter −0.0% · This fits
285/40R21 → 255/50R20
285/40R21
Diameter −0.2% · This fits
265/45R21 → 255/50R20
265/45R21
Diameter +1.2% · This fits
255/50R20 → 255/55R20
255/55R20
Diameter −3.2% · Borderline. Check clearance first
255/50R20 → 265/45R20
265/45R20
Diameter +2.2% · This fits
255/50R20 → 265/50R20
265/50R20
Diameter −1.3% · This fits
255/50R20 → 265/55R20
265/55R20
Diameter −4.6% · Borderline. Check clearance first
255/50R20 → 275/40R20
275/40R20
Diameter +4.8% · Borderline. Check clearance first
255/50R20 → 285/50R20
285/50R20
Diameter −3.8% · Borderline. Check clearance first
255/50R20 → 265/40R21
265/40R21
Diameter +2.4% · This fits
255/50R20 → 265/45R21
265/45R21
Diameter −1.2% · This fits
255/50R20 → 285/40R21
285/40R21
Diameter +0.2% · This fits
255/50R20 → 275/40R22
275/40R22
Diameter −2.0% · This fits
255/50R20 → 285/40R22
285/40R22
Diameter −3.0% · Borderline. Check clearance first
255/50R20 → 275/55R20
275/55R20
Diameter −5.9% · Too big a jump
Common questions
- What is 255/50R20 in inches?
- A 255/50R20 tire is 30.04 inches tall and 10.0 inches wide, with a 5.02-inch sidewall, mounted on a 20-inch wheel. In metric that is 763 mm tall and 255 mm wide. The circumference is 94.37 inches.
- How tall is a 255/50R20 tire?
- 30.04 inches, or 763 mm. That is the overall diameter, wheel included. It turns about 671 times per mile, which is what your speedometer counts.
- What do the numbers in 255/50R20 mean?
- 255 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 255 × 50% = 127.5 mm tall.