TireSizeCheck

265/65R18

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 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% · Good fit

265/65R18 → 265/60R18

265/60R18

Diameter +3.4% · Marginal fit — proceed with care

265/65R18 → 265/75R16

265/75R16

Diameter −0.3% · Good fit

265/65R18 → 235/80R17

235/80R17

Diameter −0.8% · Good fit

265/65R18 → 245/75R17

245/75R17

Diameter +0.3% · Good fit

265/65R18 → 255/75R17

255/75R17

Diameter −1.5% · Good fit

265/65R18 → 305/65R17

305/65R17

Diameter −3.2% · Marginal fit — proceed with care

265/65R18 → 235/65R18

235/65R18

Diameter +5.1% · Not recommended

265/65R18 → 245/65R18

245/65R18

Diameter +3.4% · Marginal fit — proceed with care

265/65R18 → 255/60R18

255/60R18

Diameter +5.0% · Not recommended

265/65R18 → 255/65R18

255/65R18

Diameter +1.6% · Good fit

265/65R18 → 255/70R18

255/70R18

Diameter −1.5% · Good fit

285/60R18 → 265/65R18

285/60R18

Diameter −0.3% · Good fit

255/70R18 → 265/65R18

255/70R18

Diameter +1.6% · Good fit

255/65R18 → 265/65R18

255/65R18

Diameter −1.6% · Good fit

275/65R18 → 265/65R18

275/65R18

Diameter +1.6% · Good fit

275/60R18 → 265/65R18

275/60R18

Diameter −1.8% · Good fit

265/60R18 → 265/65R18

265/60R18

Diameter −3.3% · Marginal fit — proceed with care

265/70R18 → 265/65R18

265/70R18

Diameter +3.3% · Marginal fit — proceed with care

305/60R18 → 265/65R18

305/60R18

Diameter +2.7% · Good fit

245/65R18 → 265/65R18

245/65R18

Diameter −3.2% · Marginal fit — proceed with care

285/65R18 → 265/65R18

285/65R18

Diameter +3.2% · Marginal fit — proceed with care

265/70R17 → 265/65R18

265/70R17

Diameter +0.1% · Good fit

265/75R16 → 265/65R18

265/75R16

Diameter +0.3% · Good fit

265/55R20 → 265/65R18

265/55R20

Diameter −0.3% · Good fit

255/60R18 → 265/65R18

255/60R18

Diameter −4.8% · Marginal fit — proceed with care

265/65R18 → 265/70R18

265/70R18

Diameter −3.2% · Marginal fit — proceed with care

265/65R18 → 275/60R18

275/60R18

Diameter +1.8% · Good fit

265/65R18 → 275/65R18

275/65R18

Diameter −1.6% · Good fit

265/65R18 → 275/70R18

275/70R18

Diameter −4.8% · Marginal fit — proceed with care

265/65R18 → 285/60R18

285/60R18

Diameter +0.3% · Good fit

265/65R18 → 285/65R18

285/65R18

Diameter −3.1% · Marginal fit — proceed with care

265/65R18 → 305/60R18

305/60R18

Diameter −2.6% · Good fit

265/65R18 → 265/55R20

265/55R20

Diameter +0.3% · Good fit

265/65R18 → 235/45R18

235/45R18

Diameter +19.9% · Not recommended

Common questions

What is the overall diameter of a 265/65R18 tire?
A 265/65R18 tire is about 31.56″ (802 mm) in overall diameter, with a sidewall height of 172.3 mm and a circumference of 99.16″.
How many revolutions per mile does a 265/65R18 tire turn?
A 265/65R18 turns roughly 639 revolutions per mile (397 per kilometre). This is the number that determines speedometer and odometer accuracy when you change tire size.
What do the numbers in 265/65R18 mean?
265 is the tread width in millimetres, 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.