Tire size

285/60R18 in inches

A 285/60R18 tire is 31.5 inches tall and 11.2 inches wide, on a 18-inch wheel. Written inch-style that is about 31.5x11.2R18 (an equivalent, not a size on sale). It rounds to a 31-inch tire.

285/60R18InchesMetric
Overall diameter (height)31.5 in799 mm
Section width11.2 in285 mm
Sidewall height6.7 in171 mm
Wheel (rim) diameter18 in457 mm
Circumference98.8 in2511 mm
Revolutions641 per mile398 per km

How it's worked out

The 60 means the sidewall is 60% of the 285 mm width: 171.0 mm, or 6.73 in. Height = wheel + 2 sidewalls = 18 + 2 x 6.73 = 31.5 in.

Similar sizes

Sizes within about 3.5% of the height of 285/60R18. The last column is your real speed at an indicated 60 mph if your speedometer was set for 285/60R18.

SizeHeightvs 285/60R18Real speed at 60 mph shown
245/75R1731.5 in+0.0%60.0 mph
265/55R2031.5 in+0.0%60.0 mph
265/65R1831.6 in+0.3%60.2 mph
285/65R1731.6 in+0.4%60.2 mph
265/70R1731.6 in+0.5%60.3 mph
295/50R2031.6 in+0.5%60.3 mph
265/75R1631.6 in+0.6%60.4 mph
285/70R1631.7 in+0.8%60.5 mph

Going bigger from 285/60R18

If 285/60R18 is your stock size, these are the commonly sold axle ratios that come closest to your stock overall gearing on bigger tires.

Your ratio nowOn 33sOn 35sOn 37s
3.213.42 exact 3.373.55 exact 3.573.73 exact 3.77
3.423.55 exact 3.593.73 exact 3.804.10 exact 4.02
3.553.73 exact 3.723.91 exact 3.954.10 exact 4.17
3.733.91 exact 3.914.10 exact 4.154.30 exact 4.39
3.914.10 exact 4.104.30 exact 4.354.56 exact 4.60
4.104.30 exact 4.304.56 exact 4.564.88 exact 4.82

Exact = your ratio x new height / 31.5. Front and rear axles must match on a 4WD. Not every ratio is made for every axle. Want more pull than stock? Go one step shorter. More in the regearing guide.

Questions

How tall is a 285/60R18 tire in inches?

31.5 inches (799 mm). That is the nominal height: the 18-inch wheel plus two 6.73-inch sidewalls.

What is 285/60R18 in inches?

31.5x11.2R18: 31.5 inches tall, 11.2 inches wide, for a 18-inch wheel.

Is 285/60R18 a 31-inch tire?

It measures 31.5 inches on paper, so it rounds to 31. Real tires vary a little by brand, load and wear, so check the maker's spec sheet if a fraction of an inch matters.

How many revolutions per mile does 285/60R18 do?

About 641 per mile (398 per km), from its nominal circumference of 98.8 inches.

Nominal dimensions, calculated from the size marking. Real tires differ slightly by brand, rim width, pressure and wear. Fitment depends on your vehicle, lift and wheels: this page doesn't say whether a size fits. Updated 2026-11-14.