235/60R15 vs 225/55R16

225/55R16 is 0.36 in (9.1 mm) shorter than 235/60R15, a −1.37% diameter difference. With the speedometer set for 235/60R15, an indicated 60 mph is 59.2 mph on 225/55R16.

Is this a safe swap?

Diameter difference −1.37%: within the ±3% guideline

By overall diameter alone, 225/55R16 falls inside the ±3% range commonly used as a guideline when replacing 235/60R15. 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.

235/60R15 vs 225/55R16 differences
Measurement	235/60R15	225/55R16	Difference	% diff
Overall diameter	26.10 in (663.0 mm)	25.74 in (653.9 mm)	−0.36 in (−9.1 mm)	−1.37%
Sidewall height	5.55 in (141.0 mm)	4.87 in (123.8 mm)	−0.68 in (−17.2 mm)	−12.23%
Section width	9.25 in (235.0 mm)	8.86 in (225.0 mm)	−0.39 in (−10.0 mm)	−4.26%
Circumference	82.00 in (2,082.9 mm)	80.88 in (2,054.3 mm)	−1.13 in (−28.6 mm)	−1.37%
Revolutions per mile	773	783	+11	+1.39%

True speed with the speedometer calibrated for 235/60R15
Indicated	Actual on 235/60R15	Actual on 225/55R16	Difference
30 mph	30.0 mph	29.6 mph	−0.4 mph
60 mph	60.0 mph	59.2 mph	−0.8 mph
75 mph	75.0 mph	74.0 mph	−1.0 mph

Ride-height change: 225/55R16 lowers the vehicle by 0.18 in (4.6 mm) at the axle (half the −9.1 mm diameter difference).

225/55R16 is 0.36 in shorter than 235/60R15 and 10 mm narrower, a 1.37% difference in overall diameter.

With the speedometer calibrated for 235/60R15, an indicated 60 mph is actually 59.2 mph on 225/55R16, and revolutions per mile change from 773 to 783.

225/55R16 mounts on a 16-inch wheel, a plus-1 fitment from the 15-inch wheel of 235/60R15.

Size pages

Other comparisons with 235/60R15

Other comparisons with 225/55R16

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