Home275/65R20 vs 285/65R20

275/65R20 vs 285/65R20

The 285/65R20 is 34.59 in tall: 0.52 in (1.5%) taller than the 275/65R20 at 34.07 in. At an indicated 60 mph you'd be doing 60.9 mph.The 285/65R20 is 878.5 mm tall: 13.0 mm (1.5%) taller than the 275/65R20 at 865.5 mm. At an indicated 100 km/h you'd be doing 101.5 km/h.

By David Owen.

in, mphmm, km/h

Each figure is rounded separately, so related figures can differ in the last digit.

These are size-code figures only. Whether a size fits, clears and carries your load depends on your vehicle and the tire, so check with a tire shop.

What changes

Only the section width changes, from 10.83 in to 11.22 in. The aspect ratio is a percentage of the width, so each sidewall grows with it, by 0.25 in, and the 285/65R20 ends up 0.52 in taller overall.

Makers' own measured diameters run 34.05 to 34.47 in for the 275/65R20 and 34.57 to 34.6 in for the 285/65R20, against the calculated 34.07 in and 34.59 in. Real tires vary by brand and tread design; the figures in the table come from the size code alone.

Speedometer and odometer

A speedometer that read true on the 275/65R20 reads low on the 285/65R20: an indicated 60 mph is a true 60.9 mph.A speedometer that read true on the 275/65R20 reads low on the 285/65R20: an indicated 100 km/h is a true 101.5 km/h.

The odometer records about 9,850 miles for every 10,000 you drive.The odometer records about 9,850 km for every 10,000 you drive.

Ground clearance and size class

Ground clearance at the axle rises by 0.26 in: half the diameter change, unloaded.Ground clearance at the axle rises by 6.5 mm: half the diameter change, unloaded. By calculated diameter the 275/65R20 is a 34-inch tire and the 285/65R20 a 35-inch tire.

See every 34-inch and 35-inch size in metric.

Same change, other sizes

The same change in diameter, width and sidewall has its own page: 275/65R18 vs 285/65R18.

Other comparisons with these sizes

• 275/65R20 vs 35x12.50R20

Compare other sizes in the calculator