TireSizesFinder

285/75R16 vs 275/70R18

275/70R18 is 0.33 in (8.3 mm) taller than 285/75R16, a +1.00% diameter difference. With the speedometer set for 285/75R16, an indicated 60 mph is 60.6 mph on 275/70R18.

Is this a safe swap?

Diameter difference +1.00%: under 1%

By overall diameter alone, 275/70R18 is a near match for 285/75R16; the speedometer changes by less than 1%. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 285/75R16 (32.83 in) vs 275/70R18 (33.16 in)285/75R1632.83 in × 11.22 in275/70R1833.16 in × 10.83 in
Side profile and tread width, drawn to the same scale.
285/75R16 vs 275/70R18 differences
Measurement285/75R16275/70R18Difference% diff
Overall diameter32.83 in (833.9 mm)33.16 in (842.2 mm)+0.33 in (+8.3 mm)+1.00%
Sidewall height8.42 in (213.8 mm)7.58 in (192.5 mm)−0.84 in (−21.2 mm)−9.94%
Section width11.22 in (285.0 mm)10.83 in (275.0 mm)−0.39 in (−10.0 mm)−3.51%
Circumference103.14 in (2,619.8 mm)104.17 in (2,645.8 mm)+1.03 in (+26.1 mm)+1.00%
Revolutions per mile614608−6−0.99%
True speed with the speedometer calibrated for 285/75R16
IndicatedActual on 285/75R16Actual on 275/70R18Difference
30 mph30.0 mph30.3 mph+0.3 mph
60 mph60.0 mph60.6 mph+0.6 mph
75 mph75.0 mph75.7 mph+0.7 mph

Ride-height change: 275/70R18 raises the vehicle by 0.16 in (4.2 mm) at the axle (half the +8.3 mm diameter difference).

275/70R18 is 0.33 in taller than 285/75R16 and 10 mm narrower, a 1.00% difference in overall diameter.

With the speedometer calibrated for 285/75R16, an indicated 60 mph is actually 60.6 mph on 275/70R18, and revolutions per mile change from 614 to 608.

275/70R18 mounts on a 18-inch wheel, a plus-2 fitment from the 16-inch wheel of 285/75R16.

Size pages

Other comparisons with 285/75R16

Other comparisons with 275/70R18

Source: Calculated from standard tire geometry formulas. Verified . How these numbers are calculated.