275/65R18
A 275/65R18 tire is 32.07 inches tall and 10.8 inches wide, with a 7.04-inch sidewall, mounted on a 18-inch wheel.
Common fitments: F-150, Silverado, Ram 1500
Overall diameter
32.07″
815 mm
Sidewall height
7.04″
178.8 mm
Tread width
275 mm
10.8″
Circumference
100.77″
8.4 ft
Revs per mile
629
391 per km
Wheel diameter
18″
aspect ratio 65%
Cross-section
- Overall diameter
- 32.07″
- Sidewall (each side)
- 7.04″
- Wheel
- 18″
275/65R18 in inches and millimeters
Every dimension of a 275/65R18, converted both ways. Calculated from the size code, accurate to about 1%.
| Measurement | Inches | Millimeters |
|---|---|---|
| Overall diameter (height) | 32.07″ | 815 mm |
| Tread width | 10.8″ | 275 mm |
| Sidewall height | 7.04″ | 178.8 mm |
| Wheel diameter | 18″ | 457 mm |
| Circumference | 100.77″ | 2559 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.
275/65R18 compared with other sizes
All 35 practical swaps involving 275/65R18 — diameter change, speedometer impact and a fit verdict for each.
275/65R18 → 275/55R20
275/55R20
Diameter +0.5% · This fits
275/65R18 → 265/75R16
265/75R16
Diameter +1.3% · This fits
275/65R18 → 285/75R16
285/75R16
Diameter −2.3% · This fits
275/65R18 → 235/80R17
235/80R17
Diameter +0.9% · This fits
275/65R18 → 255/75R17
255/75R17
Diameter +0.0% · This fits
275/65R18 → 275/70R17
275/70R17
Diameter −0.3% · This fits
275/65R18 → 305/65R17
305/65R17
Diameter −1.6% · This fits
275/65R18 → 305/70R17
305/70R17
Diameter −5.1% · Too big a jump
275/65R18 → 245/65R18
245/65R18
Diameter +5.0% · Too big a jump
275/65R18 → 255/65R18
255/65R18
Diameter +3.3% · Borderline. Check clearance first
275/65R18 → 255/70R18
255/70R18
Diameter +0.1% · This fits
275/65R18 → 265/65R18
265/65R18
Diameter +1.6% · This fits
275/65R18 → 265/70R18
265/70R18
Diameter −1.6% · This fits
275/65R18 → 275/60R18
275/60R18
Diameter +3.5% · Borderline. Check clearance first
255/70R18 → 275/65R18
255/70R18
Diameter −0.1% · This fits
305/60R18 → 275/65R18
305/60R18
Diameter +1.0% · This fits
265/65R18 → 275/65R18
265/65R18
Diameter −1.6% · This fits
285/65R18 → 275/65R18
285/65R18
Diameter +1.6% · This fits
265/70R18 → 275/65R18
265/70R18
Diameter +1.7% · This fits
285/60R18 → 275/65R18
285/60R18
Diameter −1.9% · This fits
275/60R18 → 275/65R18
275/60R18
Diameter −3.4% · Borderline. Check clearance first
275/70R18 → 275/65R18
275/70R18
Diameter +3.4% · Borderline. Check clearance first
255/65R18 → 275/65R18
255/65R18
Diameter −3.2% · Borderline. Check clearance first
275/70R17 → 275/65R18
275/70R17
Diameter +0.3% · This fits
275/55R20 → 275/65R18
275/55R20
Diameter −0.5% · This fits
245/65R18 → 275/65R18
245/65R18
Diameter −4.8% · Borderline. Check clearance first
265/60R18 → 275/65R18
265/60R18
Diameter −4.8% · Borderline. Check clearance first
255/75R17 → 275/65R18
255/75R17
Diameter −0.0% · This fits
275/65R18 → 275/70R18
275/70R18
Diameter −3.3% · Borderline. Check clearance first
275/65R18 → 285/60R18
285/60R18
Diameter +1.9% · This fits
275/65R18 → 285/65R18
285/65R18
Diameter −1.6% · This fits
275/65R18 → 285/70R18
285/70R18
Diameter −4.8% · Borderline. Check clearance first
275/65R18 → 305/60R18
305/60R18
Diameter −1.0% · This fits
275/65R18 → 305/50R20
305/50R20
Diameter +0.2% · This fits
275/65R18 → 235/45R18
235/45R18
Diameter +21.8% · Too big a jump
Common questions
- What is 275/65R18 in inches?
- A 275/65R18 tire is 32.07 inches tall and 10.8 inches wide, with a 7.04-inch sidewall, mounted on a 18-inch wheel. In metric that is 815 mm tall and 275 mm wide. The circumference is 100.77 inches.
- How tall is a 275/65R18 tire?
- 32.07 inches, or 815 mm. That is the overall diameter, wheel included. It turns about 629 times per mile, which is what your speedometer counts.
- What do the numbers in 275/65R18 mean?
- 275 is the tread width in millimeters, 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 275 × 65% = 178.8 mm tall.