Home275/65R18 vs 275/70R18

275/65R18 vs 275/70R18

The 275/70R18 is 33.16 in tall: 1.09 in (3.4%) taller than the 275/65R18 at 32.07 in. At an indicated 60 mph you'd be doing 62.0 mph.The 275/70R18 is 842.2 mm tall: 27.5 mm (3.4%) taller than the 275/65R18 at 814.7 mm. At an indicated 100 km/h you'd be doing 103.4 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

The width stays at 10.83 in; the aspect ratio goes from 65 to 70. Each sidewall goes from 7.04 in to 7.58 in, and with one sidewall above the wheel and one below, the overall diameter goes from 32.07 in to 33.16 in.

Makers' own measured diameters run 32.09 to 32.32 in for the 275/65R18 and 33.19 to 33.62 in for the 275/70R18, against the calculated 32.07 in and 33.16 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 275/65R18 reads low on the 275/70R18: an indicated 60 mph is a true 62.0 mph.A speedometer that read true on the 275/65R18 reads low on the 275/70R18: an indicated 100 km/h is a true 103.4 km/h.

The odometer records about 9,670 miles for every 10,000 you drive.The odometer records about 9,670 km for every 10,000 you drive.

Ground clearance and size class

Ground clearance at the axle rises by 0.54 in: half the diameter change, unloaded.Ground clearance at the axle rises by 13.8 mm: half the diameter change, unloaded. By calculated diameter the 275/65R18 is a 32-inch tire and the 275/70R18 a 33-inch tire.

See every 32-inch and 33-inch size in metric.

Same change, other sizes

The same change in diameter, width and sidewall has its own page: 275/55R20 vs 275/60R20.

Other comparisons with these sizes

• 275/65R18 vs 285/65R18
• 265/60R18 vs 275/65R18
• 275/70R18 vs 285/65R18

275/70R18 in inches.

Compare other sizes in the calculator