245/70R17 vs 275/65R17

275/65R17 is 0.57 inches (1.9%) taller than 245/70R17 and 1.18 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
+0.57″
275/65R17 vs 245/70R17
245/70R17275/65R17Difference
Overall diameter30.5″ 775 mm31.1″ 789 mm+0.57″ (+1.9%)
Section width9.6″ 245 mm10.8″ 275 mm+1.18″
Sidewall height6.75″ 172 mm7.04″ 179 mm+0.29″
Wheel (rim) diameter17″17″same
Circumference95.8″ 2434 mm97.6″ 2480 mm+1.8″
Revolutions per mile661649−12
Ground clearance+0.29″
245/70R1730.5″ × 9.6″30.5″275/65R1731.1″ × 10.8″31.1″
Drawn to scale: side view and tread width.

275/65R17 is 0.57″ taller (1.9%) and 1.18″ wider than 245/70R17. With a speedometer set up for 245/70R17, an indicated 60 mph is really 61.1 mph on 275/65R17, so the gauge reads 1.9% low. Ground clearance at the axle changes by +0.29″.

A 1.9% 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 275/65R17
30 mph30.6 mph
45 mph45.8 mph
60 mph61.1 mph
70 mph71.3 mph
80 mph81.5 mph

What changes when you switch to 275/65R17

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 275/65R17 than 245/70R17?

275/65R17 is 0.57 inches (1.9%) taller and 1.18 inches wider: 31.1" × 10.8" versus 30.5" × 9.6".

Will 275/65R17 change my speedometer?

Yes, by 1.9%. Going from 245/70R17 to 275/65R17, an indicated 60 mph is about 61.1 mph.

Can I replace 245/70R17 with 275/65R17?

Often, yes: the height difference is within the ±3% most tire shops accept. Both fit a 17" wheel; confirm the rim width, load index and clearance for your vehicle.

Do I need to regear going from 245/70R17 to 275/65R17?

Usually not for a 1.9% change. With 3.73 gears, the 275/65R17 acts like 3.66.

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