TireSizeCheck

255/60R18

Overall diameter

30.05″

763 mm

Sidewall height

6.02″

153.0 mm

Tread width

255 mm

10.0″

Circumference

94.40″

7.9 ft

Revs per mile

671

417 per km

Wheel diameter

18″

aspect ratio 60%

Cross-section

Overall diameter
30.05″
Sidewall (each side)
6.02″
Wheel
18″

255/60R18 compared with other sizes

All 31 practical swaps involving 255/60R18 — diameter change, speedometer impact and a fit verdict for each.

255/60R18 → 245/75R16

245/75R16

Diameter −1.4% · Good fit

255/60R18 → 235/60R18

235/60R18

Diameter +3.2% · Marginal fit — proceed with care

255/60R18 → 255/55R18

255/55R18

Diameter +3.5% · Marginal fit — proceed with care

255/60R18 → 265/60R18

265/60R18

Diameter −1.5% · Good fit

255/60R18 → 245/70R16

245/70R16

Diameter +1.8% · Good fit

255/60R18 → 255/70R16

255/70R16

Diameter −0.0% · Good fit

255/60R18 → 255/65R17

255/65R17

Diameter −0.0% · Good fit

255/60R18 → 225/60R18

225/60R18

Diameter +5.0% · Marginal fit — proceed with care

255/60R18 → 235/65R18

235/65R18

Diameter +0.1% · Good fit

255/60R18 → 245/60R18

245/60R18

Diameter +1.6% · Good fit

255/60R18 → 245/65R18

245/65R18

Diameter −1.6% · Good fit

235/65R18 → 255/60R18

235/65R18

Diameter −0.1% · Good fit

245/60R18 → 255/60R18

245/60R18

Diameter −1.6% · Good fit

265/60R18 → 255/60R18

265/60R18

Diameter +1.6% · Good fit

245/65R18 → 255/60R18

245/65R18

Diameter +1.6% · Good fit

255/55R18 → 255/60R18

255/55R18

Diameter −3.3% · Marginal fit — proceed with care

255/65R18 → 255/60R18

255/65R18

Diameter +3.3% · Marginal fit — proceed with care

235/60R18 → 255/60R18

235/60R18

Diameter −3.1% · Marginal fit — proceed with care

275/60R18 → 255/60R18

275/60R18

Diameter +3.1% · Marginal fit — proceed with care

255/65R17 → 255/60R18

255/65R17

Diameter +0.0% · Good fit

255/70R16 → 255/60R18

255/70R16

Diameter +0.0% · Good fit

255/50R20 → 255/60R18

255/50R20

Diameter −0.0% · Good fit

225/60R18 → 255/60R18

225/60R18

Diameter −4.7% · Marginal fit — proceed with care

285/60R18 → 255/60R18

285/60R18

Diameter +4.7% · Marginal fit — proceed with care

265/65R18 → 255/60R18

265/65R18

Diameter +5.0% · Not recommended

255/60R18 → 255/65R18

255/65R18

Diameter −3.2% · Marginal fit — proceed with care

255/60R18 → 265/65R18

265/65R18

Diameter −4.8% · Marginal fit — proceed with care

255/60R18 → 275/60R18

275/60R18

Diameter −3.0% · Marginal fit — proceed with care

255/60R18 → 285/60R18

285/60R18

Diameter −4.5% · Marginal fit — proceed with care

255/60R18 → 255/50R20

255/50R20

Diameter +0.0% · Good fit

255/60R18 → 235/45R18

235/45R18

Diameter +14.1% · Not recommended

Common questions

What is the overall diameter of a 255/60R18 tire?
A 255/60R18 tire is about 30.05″ (763 mm) in overall diameter, with a sidewall height of 153.0 mm and a circumference of 94.40″.
How many revolutions per mile does a 255/60R18 tire turn?
A 255/60R18 turns roughly 671 revolutions per mile (417 per kilometre). This is the number that determines speedometer and odometer accuracy when you change tire size.
What do the numbers in 255/60R18 mean?
255 is the tread width in millimetres, 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 255 × 60% = 153.0 mm tall.