215/70R16 vs 245/55R17

245/55R17 is 0.24 in (6.1 mm) shorter than 215/70R16, a −0.86% diameter difference. With the speedometer set for 215/70R16, an indicated 60 mph is 59.5 mph on 245/55R17.

Is this a safe swap?

Diameter difference −0.86%: under 1%

By overall diameter alone, 245/55R17 is a near match for 215/70R16; the speedometer changes by less than 1%. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

Side profile and tread width, drawn to the same scale.

215/70R16 vs 245/55R17 differences
Measurement	215/70R16	245/55R17	Difference	% diff
Overall diameter	27.85 in (707.4 mm)	27.61 in (701.3 mm)	−0.24 in (−6.1 mm)	−0.86%
Sidewall height	5.93 in (150.5 mm)	5.31 in (134.8 mm)	−0.62 in (−15.7 mm)	−10.47%
Section width	8.46 in (215.0 mm)	9.65 in (245.0 mm)	+1.18 in (+30.0 mm)	+13.95%
Circumference	87.49 in (2,222.4 mm)	86.74 in (2,203.2 mm)	−0.75 in (−19.2 mm)	−0.86%
Revolutions per mile	724	730	+6	+0.87%

True speed with the speedometer calibrated for 215/70R16
Indicated	Actual on 215/70R16	Actual on 245/55R17	Difference
30 mph	30.0 mph	29.7 mph	−0.3 mph
60 mph	60.0 mph	59.5 mph	−0.5 mph
75 mph	75.0 mph	74.4 mph	−0.6 mph

Ride-height change: 245/55R17 lowers the vehicle by 0.12 in (3.1 mm) at the axle (half the −6.1 mm diameter difference).

245/55R17 is 0.24 in shorter than 215/70R16 and 30 mm wider, a 0.86% difference in overall diameter.

With the speedometer calibrated for 215/70R16, an indicated 60 mph is actually 59.5 mph on 245/55R17, and revolutions per mile change from 724 to 730.

245/55R17 mounts on a 17-inch wheel, a plus-1 fitment from the 16-inch wheel of 215/70R16.

Size pages

Other comparisons with 215/70R16

Other comparisons with 245/55R17

Source: Calculated from standard tire geometry formulas. Verified 2026-09-27. How these numbers are calculated.