275/65R18 vs 265/70R18

265/70R18 is 0.53 inches (1.7%) taller than 275/65R18 and 0.39 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
+0.53″
265/70R18 vs 275/65R18
275/65R18265/70R18Difference
Overall diameter32.1″ 815 mm32.6″ 828 mm+0.53″ (+1.7%)
Section width10.8″ 275 mm10.4″ 265 mm−0.39″
Sidewall height7.04″ 179 mm7.30″ 186 mm+0.27″
Wheel (rim) diameter18″18″same
Circumference100.8″ 2559 mm102.4″ 2602 mm+1.7″
Revolutions per mile629619−10
Ground clearance+0.27″
275/65R1832.1″ × 10.8″32.1″265/70R1832.6″ × 10.4″32.6″
Drawn to scale: side view and tread width.

265/70R18 is 0.53″ taller (1.7%) and 0.39″ narrower than 275/65R18. With a speedometer set up for 275/65R18, an indicated 60 mph is really 61.0 mph on 265/70R18, so the gauge reads 1.7% low. Ground clearance at the axle changes by +0.27″.

A 1.7% difference is within the ±3% that tire shops commonly accept without recalibrating the speedometer. Check clearance if the new tire is wider or taller.

Speedometer showsReal speed on 265/70R18
30 mph30.5 mph
45 mph45.7 mph
60 mph61.0 mph
70 mph71.2 mph
80 mph81.3 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 275/65R18?

265/70R18 is 0.53 inches (1.7%) taller and 0.39 inches narrower: 32.6" × 10.4" versus 32.1" × 10.8".

Will 265/70R18 change my speedometer?

Yes, by 1.7%. Going from 275/65R18 to 265/70R18, an indicated 60 mph is about 61.0 mph.

Can I replace 275/65R18 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 275/65R18 to 265/70R18?

Usually not for a 1.7% change. With 3.73 gears, the 265/70R18 acts like 3.67.

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