TireSizesFinder

285/65R18 vs 265/60R20

265/60R20 is 0.07 in (1.7 mm) shorter than 285/65R18, a −0.21% diameter difference. With the speedometer set for 285/65R18, an indicated 60 mph is 59.9 mph on 265/60R20.

Is this a safe swap?

Diameter difference −0.21%: under 1%

By overall diameter alone, 265/60R20 is a near match for 285/65R18; 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: 285/65R18 (32.59 in) vs 265/60R20 (32.52 in)285/65R1832.59 in × 11.22 in265/60R2032.52 in × 10.43 in
Side profile and tread width, drawn to the same scale.
285/65R18 vs 265/60R20 differences
Measurement285/65R18265/60R20Difference% diff
Overall diameter32.59 in (827.7 mm)32.52 in (826.0 mm)−0.07 in (−1.7 mm)−0.21%
Sidewall height7.29 in (185.3 mm)6.26 in (159.0 mm)−1.03 in (−26.2 mm)−14.17%
Section width11.22 in (285.0 mm)10.43 in (265.0 mm)−0.79 in (−20.0 mm)−7.02%
Circumference102.37 in (2,600.3 mm)102.16 in (2,595.0 mm)−0.21 in (−5.3 mm)−0.21%
Revolutions per mile619620+1+0.21%
True speed with the speedometer calibrated for 285/65R18
IndicatedActual on 285/65R18Actual on 265/60R20Difference
30 mph30.0 mph29.9 mph−0.1 mph
60 mph60.0 mph59.9 mph−0.1 mph
75 mph75.0 mph74.8 mph−0.2 mph

Ride-height change: 265/60R20 lowers the vehicle by 0.03 in (0.9 mm) at the axle (half the −1.7 mm diameter difference).

265/60R20 is 0.07 in shorter than 285/65R18 and 20 mm narrower, a 0.21% difference in overall diameter.

With the speedometer calibrated for 285/65R18, an indicated 60 mph is actually 59.9 mph on 265/60R20, and revolutions per mile change from 619 to 620.

265/60R20 mounts on a 20-inch wheel, a plus-2 fitment from the 18-inch wheel of 285/65R18.

Size pages

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Other comparisons with 265/60R20

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