195/55R16 vs 225/40R17

225/40R17 is 0.36 in (9.1 mm) shorter than 195/55R16, a −1.47% diameter difference. With the speedometer set for 195/55R16, an indicated 60 mph is 59.1 mph on 225/40R17.

Is this a safe swap?

Diameter difference −1.47%: within the ±3% guideline

By overall diameter alone, 225/40R17 falls inside the ±3% range commonly used as a guideline when replacing 195/55R16. 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.

195/55R16 vs 225/40R17 differences
Measurement	195/55R16	225/40R17	Difference	% diff
Overall diameter	24.44 in (620.9 mm)	24.09 in (611.8 mm)	−0.36 in (−9.1 mm)	−1.47%
Sidewall height	4.22 in (107.3 mm)	3.54 in (90.0 mm)	−0.68 in (−17.2 mm)	−16.08%
Section width	7.68 in (195.0 mm)	8.86 in (225.0 mm)	+1.18 in (+30.0 mm)	+15.38%
Circumference	76.80 in (1,950.6 mm)	75.67 in (1,922.0 mm)	−1.13 in (−28.6 mm)	−1.47%
Revolutions per mile	825	837	+12	+1.49%

True speed with the speedometer calibrated for 195/55R16
Indicated	Actual on 195/55R16	Actual on 225/40R17	Difference
30 mph	30.0 mph	29.6 mph	−0.4 mph
60 mph	60.0 mph	59.1 mph	−0.9 mph
75 mph	75.0 mph	73.9 mph	−1.1 mph

Ride-height change: 225/40R17 lowers the vehicle by 0.18 in (4.6 mm) at the axle (half the −9.1 mm diameter difference).

225/40R17 is 0.36 in shorter than 195/55R16 and 30 mm wider, a 1.47% difference in overall diameter.

With the speedometer calibrated for 195/55R16, an indicated 60 mph is actually 59.1 mph on 225/40R17, and revolutions per mile change from 825 to 837.

225/40R17 mounts on a 17-inch wheel, a plus-1 fitment from the 16-inch wheel of 195/55R16.

Size pages

Other comparisons with 195/55R16

Other comparisons with 225/40R17

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