265/65R18 vs 285/65R18

285/65R18 is 1.02 inches (3.2%) taller than 265/65R18 and 0.79 inches wider. Here are both sizes side by side, drawn to scale.

Last updated · Calculated from the sidewall code · Sources

Tire sizes

Type it as it appears on the sidewall: 275/60R20, LT265/70R17 or 33x12.50R20.

Difference in height
+1.02″
285/65R18 vs 265/65R18
265/65R18285/65R18Difference
Overall diameter31.6″ 802 mm32.6″ 828 mm+1.02″ (+3.2%)
Section width10.4″ 265 mm11.2″ 285 mm+0.79″
Sidewall height6.78″ 172 mm7.29″ 185 mm+0.51″
Wheel (rim) diameter18″18″same
Circumference99.2″ 2519 mm102.4″ 2600 mm+3.2″
Revolutions per mile639619−20
Ground clearance+0.51″
265/65R1831.6″ × 10.4″31.6″285/65R1832.6″ × 11.2″32.6″
Drawn to scale: side view and tread width.

285/65R18 is 1.02″ taller (3.2%) and 0.79″ wider than 265/65R18. With a speedometer set up for 265/65R18, an indicated 60 mph is really 61.9 mph on 285/65R18, so the gauge reads 3.2% low. Ground clearance at the axle changes by +0.51″.

A 3.2% difference is more than the ±3% shops commonly use as a limit: plan to recalibrate the speedometer, check clearance (and lift or leveling needs), and consider regearing if it's a big jump.

Speedometer showsReal speed on 285/65R18
30 mph31.0 mph
45 mph46.5 mph
60 mph61.9 mph
70 mph72.3 mph
80 mph82.6 mph

What changes when you switch to 285/65R18

Sizes are theoretical, from the sidewall code. The same size can differ by a few tenths of an inch between brands and tread patterns; check the maker’s spec sheet for the exact model.

Other comparisons

Frequently asked questions

How much bigger is 285/65R18 than 265/65R18?

285/65R18 is 1.02 inches (3.2%) taller and 0.79 inches wider: 32.6" × 11.2" versus 31.6" × 10.4".

Will 285/65R18 change my speedometer?

Yes, by 3.2%. Going from 265/65R18 to 285/65R18, an indicated 60 mph is about 61.9 mph.

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

Possibly, but the height difference is over 3%, so check clearance and plan to recalibrate the speedometer. Both fit an 18" wheel; confirm the rim width, load index and clearance for your vehicle.

Do I need to regear going from 265/65R18 to 285/65R18?

Usually not for a 3.2% change. With 3.73 gears, the 285/65R18 acts like 3.61.

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