235/65R16 vs 225/70R16

225/70R16 is 0.37 in (9.5 mm) taller than 235/65R16, a +1.33% diameter difference. With the speedometer set for 235/65R16, an indicated 60 mph is 60.8 mph on 225/70R16.

Is this a safe swap?

Diameter difference +1.33%: within the ±3% guideline

By overall diameter alone, 225/70R16 falls inside the ±3% range commonly used as a guideline when replacing 235/65R16. 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.

235/65R16 vs 225/70R16 differences
Measurement	235/65R16	225/70R16	Difference	% diff
Overall diameter	28.03 in (711.9 mm)	28.40 in (721.4 mm)	+0.37 in (+9.5 mm)	+1.33%
Sidewall height	6.01 in (152.8 mm)	6.20 in (157.5 mm)	+0.19 in (+4.8 mm)	+3.11%
Section width	9.25 in (235.0 mm)	8.86 in (225.0 mm)	−0.39 in (−10.0 mm)	−4.26%
Circumference	88.05 in (2,236.5 mm)	89.23 in (2,266.3 mm)	+1.18 in (+29.8 mm)	+1.33%
Revolutions per mile	720	710	−9	−1.32%

True speed with the speedometer calibrated for 235/65R16
Indicated	Actual on 235/65R16	Actual on 225/70R16	Difference
30 mph	30.0 mph	30.4 mph	+0.4 mph
60 mph	60.0 mph	60.8 mph	+0.8 mph
75 mph	75.0 mph	76.0 mph	+1.0 mph

Ride-height change: 225/70R16 raises the vehicle by 0.19 in (4.8 mm) at the axle (half the +9.5 mm diameter difference).

225/70R16 is 0.37 in taller than 235/65R16 and 10 mm narrower, a 1.33% difference in overall diameter.

With the speedometer calibrated for 235/65R16, an indicated 60 mph is actually 60.8 mph on 225/70R16, and revolutions per mile change from 720 to 710.

Both sizes mount on 16-inch wheels.

Size pages

Other comparisons with 235/65R16

Other comparisons with 225/70R16

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