285/55R20 vs 275/60R20

275/60R20 is 0.65 inches (2.0%) taller than 285/55R20 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
+0.65″
275/60R20 vs 285/55R20
285/55R20275/60R20Difference
Overall diameter32.3″ 822 mm33.0″ 838 mm+0.65″ (+2.0%)
Section width11.2″ 285 mm10.8″ 275 mm−0.39″
Sidewall height6.17″ 157 mm6.50″ 165 mm+0.32″
Wheel (rim) diameter20″20″same
Circumference101.6″ 2581 mm103.6″ 2633 mm+2.0″
Revolutions per mile624611−12
Ground clearance+0.32″
285/55R2032.3″ × 11.2″32.3″275/60R2033.0″ × 10.8″33.0″
Drawn to scale: side view and tread width.

275/60R20 is 0.65″ taller (2.0%) and 0.39″ narrower than 285/55R20. With a speedometer set up for 285/55R20, an indicated 60 mph is really 61.2 mph on 275/60R20, so the gauge reads 2.0% low. Ground clearance at the axle changes by +0.32″.

A 2.0% 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 275/60R20
30 mph30.6 mph
45 mph45.9 mph
60 mph61.2 mph
70 mph71.4 mph
80 mph81.6 mph

What changes when you switch to 275/60R20

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 275/60R20 than 285/55R20?

275/60R20 is 0.65 inches (2.0%) taller and 0.39 inches narrower: 33.0" × 10.8" versus 32.3" × 11.2".

Will 275/60R20 change my speedometer?

Yes, by 2.0%. Going from 285/55R20 to 275/60R20, an indicated 60 mph is about 61.2 mph.

Can I replace 285/55R20 with 275/60R20?

Often, yes: the height difference is within the ±3% most tire shops accept. Both fit a 20" wheel; confirm the rim width, load index and clearance for your vehicle.

Do I need to regear going from 285/55R20 to 275/60R20?

Usually not for a 2.0% change. With 3.73 gears, the 275/60R20 acts like 3.66.

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