285/65R18 vs 265/70R18

265/70R18 is 0.02 inches (0.1%) taller than 285/65R18 and 0.79 inches narrower. 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
+0.02″
265/70R18 vs 285/65R18
285/65R18265/70R18Difference
Overall diameter32.6″ 828 mm32.6″ 828 mm+0.02″ (+0.1%)
Section width11.2″ 285 mm10.4″ 265 mm−0.79″
Sidewall height7.29″ 185 mm7.30″ 186 mm+0.01″
Wheel (rim) diameter18″18″same
Circumference102.4″ 2600 mm102.4″ 2602 mm+0.1″
Revolutions per mile619619−0
Ground clearance+0.01″
285/65R1832.6″ × 11.2″32.6″265/70R1832.6″ × 10.4″32.6″
Drawn to scale: side view and tread width.

265/70R18 is 0.02″ taller (0.1%) and 0.79″ narrower than 285/65R18. Your speedometer stays accurate.

A 0.1% diameter difference is small: most people treat these sizes as interchangeable.

Speedometer showsReal speed on 265/70R18
30 mph30.0 mph
45 mph45.0 mph
60 mph60.0 mph
70 mph70.0 mph
80 mph80.0 mph

What changes when you switch to 265/70R18

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 265/70R18 than 285/65R18?

265/70R18 is 0.02 inches (0.1%) taller and 0.79 inches narrower: 32.6" × 10.4" versus 32.6" × 11.2".

Will 265/70R18 change my speedometer?

No, the diameters are practically the same.

Can I replace 285/65R18 with 265/70R18?

Often, yes: the height difference is within the ±3% most tire shops accept. Both fit an 18" wheel; confirm the rim width, load index and clearance for your vehicle.

Do I need to regear going from 285/65R18 to 265/70R18?

Usually not for a 0.1% change. With 3.73 gears, the 265/70R18 acts like 3.73.

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