TireSizeCheck

275/60R18

A 275/60R18 tire is 30.99 inches tall and 10.8 inches wide, with a 6.50-inch sidewall, mounted on a 18-inch wheel.

Overall diameter

30.99″

787 mm

Sidewall height

6.50″

165.0 mm

Tread width

275 mm

10.8″

Circumference

97.36″

8.1 ft

Revs per mile

651

404 per km

Wheel diameter

18″

aspect ratio 60%

Cross-section

Overall diameter
30.99″
Sidewall (each side)
6.50″
Wheel
18″

275/60R18 in inches and millimeters

Every dimension of a 275/60R18, converted both ways. Calculated from the size code, accurate to about 1%.

Measurement Inches Millimeters
Overall diameter (height) 30.99″ 787 mm
Tread width 10.8″ 275 mm
Sidewall height 6.50″ 165.0 mm
Wheel diameter 18″ 457 mm
Circumference 97.36″ 2473 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.

275/60R18 compared with other sizes

All 34 practical swaps involving 275/60R18 — diameter change, speedometer impact and a fit verdict for each.

275/60R18 → 265/70R16

265/70R16

Diameter +1.3% · This fits

275/60R18 → 265/60R18

265/60R18

Diameter +1.5% · This fits

275/60R18 → 255/70R17

255/70R17

Diameter −0.2% · This fits

275/60R18 → 275/65R17

275/65R17

Diameter −0.3% · This fits

275/60R18 → 235/65R18

235/65R18

Diameter +3.2% · Borderline. Check clearance first

275/60R18 → 245/60R18

245/60R18

Diameter +4.8% · Borderline. Check clearance first

275/60R18 → 245/65R18

245/65R18

Diameter +1.5% · This fits

275/60R18 → 255/60R18

255/60R18

Diameter +3.1% · Borderline. Check clearance first

275/60R18 → 255/65R18

255/65R18

Diameter −0.2% · This fits

275/60R18 → 255/70R18

255/70R18

Diameter −3.3% · Borderline. Check clearance first

275/60R18 → 265/65R18

265/65R18

Diameter −1.8% · This fits

275/60R18 → 265/70R18

265/70R18

Diameter −5.0% · Borderline. Check clearance first

255/65R18 → 275/60R18

255/65R18

Diameter +0.2% · This fits

245/65R18 → 275/60R18

245/65R18

Diameter −1.5% · This fits

265/60R18 → 275/60R18

265/60R18

Diameter −1.5% · This fits

285/60R18 → 275/60R18

285/60R18

Diameter +1.5% · This fits

265/65R18 → 275/60R18

265/65R18

Diameter +1.8% · This fits

275/65R18 → 275/60R18

275/65R18

Diameter +3.5% · Borderline. Check clearance first

255/60R18 → 275/60R18

255/60R18

Diameter −3.0% · Borderline. Check clearance first

235/65R18 → 275/60R18

235/65R18

Diameter −3.1% · Borderline. Check clearance first

255/70R18 → 275/60R18

255/70R18

Diameter +3.4% · Borderline. Check clearance first

275/65R17 → 275/60R18

275/65R17

Diameter +0.3% · This fits

275/55R19 → 275/60R18

275/55R19

Diameter −0.3% · This fits

305/60R18 → 275/60R18

305/60R18

Diameter +4.6% · Borderline. Check clearance first

245/60R18 → 275/60R18

245/60R18

Diameter −4.6% · Borderline. Check clearance first

285/65R18 → 275/60R18

285/65R18

Diameter +5.1% · Too big a jump

275/60R18 → 275/65R18

275/65R18

Diameter −3.4% · Borderline. Check clearance first

275/60R18 → 285/60R18

285/60R18

Diameter −1.5% · This fits

275/60R18 → 285/65R18

285/65R18

Diameter −4.9% · Borderline. Check clearance first

275/60R18 → 305/60R18

305/60R18

Diameter −4.4% · Borderline. Check clearance first

275/60R18 → 255/60R19

255/60R19

Diameter −0.2% · This fits

275/60R18 → 275/55R19

275/55R19

Diameter +0.3% · This fits

275/60R18 → 255/55R20

255/55R20

Diameter −0.2% · This fits

275/60R18 → 235/45R18

235/45R18

Diameter +17.7% · Too big a jump

Common questions

What is 275/60R18 in inches?
A 275/60R18 tire is 30.99 inches tall and 10.8 inches wide, with a 6.50-inch sidewall, mounted on a 18-inch wheel. In metric that is 787 mm tall and 275 mm wide. The circumference is 97.36 inches.
How tall is a 275/60R18 tire?
30.99 inches, or 787 mm. That is the overall diameter, wheel included. It turns about 651 times per mile, which is what your speedometer counts.
What do the numbers in 275/60R18 mean?
275 is the tread width in millimeters, 60 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 × 60% = 165.0 mm tall.