TireSizeCheck

265/65R18

A 265/65R18 tire is 31.56 inches tall and 10.4 inches wide, with a 6.78-inch sidewall, mounted on a 18-inch wheel.

Overall diameter

31.56″

802 mm

Sidewall height

6.78″

172.3 mm

Tread width

265 mm

10.4″

Circumference

99.16″

8.3 ft

Revs per mile

639

397 per km

Wheel diameter

18″

aspect ratio 65%

Cross-section

Overall diameter
31.56″
Sidewall (each side)
6.78″
Wheel
18″

265/65R18 in inches and millimeters

Every dimension of a 265/65R18, converted both ways. Calculated from the size code, accurate to about 1%.

Measurement Inches Millimeters
Overall diameter (height) 31.56″ 802 mm
Tread width 10.4″ 265 mm
Sidewall height 6.78″ 172.3 mm
Wheel diameter 18″ 457 mm
Circumference 99.16″ 2519 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.

265/65R18 compared with other sizes

All 35 practical swaps involving 265/65R18 — diameter change, speedometer impact and a fit verdict for each.

265/65R18 → 265/70R17

265/70R17

Diameter −0.1% · This fits

265/65R18 → 265/60R18

265/60R18

Diameter +3.4% · Borderline. Check clearance first

265/65R18 → 265/75R16

265/75R16

Diameter −0.3% · This fits

265/65R18 → 235/80R17

235/80R17

Diameter −0.8% · This fits

265/65R18 → 245/75R17

245/75R17

Diameter +0.3% · This fits

265/65R18 → 255/75R17

255/75R17

Diameter −1.5% · This fits

265/65R18 → 305/65R17

305/65R17

Diameter −3.2% · Borderline. Check clearance first

265/65R18 → 235/65R18

235/65R18

Diameter +5.1% · Too big a jump

265/65R18 → 245/65R18

245/65R18

Diameter +3.4% · Borderline. Check clearance first

265/65R18 → 255/60R18

255/60R18

Diameter +5.0% · Too big a jump

265/65R18 → 255/65R18

255/65R18

Diameter +1.6% · This fits

265/65R18 → 255/70R18

255/70R18

Diameter −1.5% · This fits

285/60R18 → 265/65R18

285/60R18

Diameter −0.3% · This fits

255/70R18 → 265/65R18

255/70R18

Diameter +1.6% · This fits

255/65R18 → 265/65R18

255/65R18

Diameter −1.6% · This fits

275/65R18 → 265/65R18

275/65R18

Diameter +1.6% · This fits

275/60R18 → 265/65R18

275/60R18

Diameter −1.8% · This fits

265/60R18 → 265/65R18

265/60R18

Diameter −3.3% · Borderline. Check clearance first

265/70R18 → 265/65R18

265/70R18

Diameter +3.3% · Borderline. Check clearance first

305/60R18 → 265/65R18

305/60R18

Diameter +2.7% · This fits

245/65R18 → 265/65R18

245/65R18

Diameter −3.2% · Borderline. Check clearance first

285/65R18 → 265/65R18

285/65R18

Diameter +3.2% · Borderline. Check clearance first

265/70R17 → 265/65R18

265/70R17

Diameter +0.1% · This fits

265/75R16 → 265/65R18

265/75R16

Diameter +0.3% · This fits

265/55R20 → 265/65R18

265/55R20

Diameter −0.3% · This fits

255/60R18 → 265/65R18

255/60R18

Diameter −4.8% · Borderline. Check clearance first

265/65R18 → 265/70R18

265/70R18

Diameter −3.2% · Borderline. Check clearance first

265/65R18 → 275/60R18

275/60R18

Diameter +1.8% · This fits

265/65R18 → 275/65R18

275/65R18

Diameter −1.6% · This fits

265/65R18 → 275/70R18

275/70R18

Diameter −4.8% · Borderline. Check clearance first

265/65R18 → 285/60R18

285/60R18

Diameter +0.3% · This fits

265/65R18 → 285/65R18

285/65R18

Diameter −3.1% · Borderline. Check clearance first

265/65R18 → 305/60R18

305/60R18

Diameter −2.6% · This fits

265/65R18 → 265/55R20

265/55R20

Diameter +0.3% · This fits

265/65R18 → 235/45R18

235/45R18

Diameter +19.9% · Too big a jump

Common questions

What is 265/65R18 in inches?
A 265/65R18 tire is 31.56 inches tall and 10.4 inches wide, with a 6.78-inch sidewall, mounted on a 18-inch wheel. In metric that is 802 mm tall and 265 mm wide. The circumference is 99.16 inches.
How tall is a 265/65R18 tire?
31.56 inches, or 802 mm. That is the overall diameter, wheel included. It turns about 639 times per mile, which is what your speedometer counts.
What do the numbers in 265/65R18 mean?
265 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 265 × 65% = 172.3 mm tall.