265/65R18 vs 285/65R18

285/65R18 is 1.0" taller than 265/65R18 (3.2%)

Diameter difference+3.24%diameter 31.56" → 32.59"
265/65R18285/65R18
265/65R18285/65R18Difference
Overall diameter31.56"32.59"+1.02"
Section width10.43"11.22"+0.79"
Sidewall height6.78"7.29"+0.51"
Circumference99.2"102.4"+3.2"
Revolutions per mile639619−20
Wheel diameter18"18"±0"

Speedometer

ShowsActualDiff
30 mph31.0 mph+1.0
45 mph46.5 mph+1.5
60 mph61.9 mph+1.9
70 mph72.3 mph+2.3
80 mph82.6 mph+2.6

Gear ratio to match

CurrentEquivalent
3.423.53
3.553.67
3.733.85
4.104.23

285/65R18 is 1.02" taller than 265/65R18, a +3.24% change in diameter. That is more than the 3% many tire shops use as a limit, so plan on recalibrating the speedometer and checking ABS and stability control.

Ground clearance changes by 0.51" (half the diameter change), and the tire needs 0.51" more room above it.

285/65R18 is 0.79" wider. On the same wheel offset about half of that, 0.39", moves toward the suspension and half toward the fender.

Both fit a 18" wheel; the sidewall is 0.51" taller on 285/65R18.

Details: 265/65R18 in inches · 285/65R18 in inches · change sizes in the calculator

FAQ

What is the difference between 265/65R18 and 285/65R18?

285/65R18 is 1.02" taller (+3.24%) and 0.79" wider than 265/65R18.

Will 285/65R18 change my speedometer?

Yes, by +3.24%. When the speedometer shows 60 mph you would be going 61.9 mph.

Can I replace 265/65R18 with 285/65R18?

It is a +3.2% diameter change, larger than the common 3% guideline, so check clearance and plan to recalibrate.