235/70R15 vs 225/70R16

225/70R16 is 0.45 in (11.4 mm) taller than 235/70R15, a +1.61% diameter difference. With the speedometer set for 235/70R15, an indicated 60 mph is 61.0 mph on 225/70R16.

Is this a safe swap?

Diameter difference +1.61%: within the ±3% guideline

By overall diameter alone, 225/70R16 falls inside the ±3% range commonly used as a guideline when replacing 235/70R15. 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.

235/70R15 vs 225/70R16 differences
Measurement	235/70R15	225/70R16	Difference	% diff
Overall diameter	27.95 in (710.0 mm)	28.40 in (721.4 mm)	+0.45 in (+11.4 mm)	+1.61%
Sidewall height	6.48 in (164.5 mm)	6.20 in (157.5 mm)	−0.28 in (−7.0 mm)	−4.26%
Section width	9.25 in (235.0 mm)	8.86 in (225.0 mm)	−0.39 in (−10.0 mm)	−4.26%
Circumference	87.82 in (2,230.5 mm)	89.23 in (2,266.3 mm)	+1.41 in (+35.8 mm)	+1.61%
Revolutions per mile	722	710	−11	−1.58%

True speed with the speedometer calibrated for 235/70R15
Indicated	Actual on 235/70R15	Actual on 225/70R16	Difference
30 mph	30.0 mph	30.5 mph	+0.5 mph
60 mph	60.0 mph	61.0 mph	+1.0 mph
75 mph	75.0 mph	76.2 mph	+1.2 mph

Ride-height change: 225/70R16 raises the vehicle by 0.22 in (5.7 mm) at the axle (half the +11.4 mm diameter difference).

225/70R16 is 0.45 in taller than 235/70R15 and 10 mm narrower, a 1.61% difference in overall diameter.

With the speedometer calibrated for 235/70R15, an indicated 60 mph is actually 61.0 mph on 225/70R16, and revolutions per mile change from 722 to 710.

225/70R16 mounts on a 16-inch wheel, a plus-1 fitment from the 15-inch wheel of 235/70R15.

Size pages

Other comparisons with 235/70R15

Other comparisons with 225/70R16

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