215/75R15 vs 225/75R15

225/75R15 is 0.59 in (15.0 mm) taller than 215/75R15, a +2.13% diameter difference. With the speedometer set for 215/75R15, an indicated 60 mph is 61.3 mph on 225/75R15.

Is this a safe swap?

Diameter difference +2.13%: within the ±3% guideline

By overall diameter alone, 225/75R15 falls inside the ±3% range commonly used as a guideline when replacing 215/75R15. 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.

215/75R15 vs 225/75R15 differences
Measurement	215/75R15	225/75R15	Difference	% diff
Overall diameter	27.70 in (703.5 mm)	28.29 in (718.5 mm)	+0.59 in (+15.0 mm)	+2.13%
Sidewall height	6.35 in (161.3 mm)	6.64 in (168.8 mm)	+0.30 in (+7.5 mm)	+4.65%
Section width	8.46 in (215.0 mm)	8.86 in (225.0 mm)	+0.39 in (+10.0 mm)	+4.65%
Circumference	87.01 in (2,210.1 mm)	88.87 in (2,257.2 mm)	+1.86 in (+47.1 mm)	+2.13%
Revolutions per mile	728	713	−15	−2.09%

True speed with the speedometer calibrated for 215/75R15
Indicated	Actual on 215/75R15	Actual on 225/75R15	Difference
30 mph	30.0 mph	30.6 mph	+0.6 mph
60 mph	60.0 mph	61.3 mph	+1.3 mph
75 mph	75.0 mph	76.6 mph	+1.6 mph

Ride-height change: 225/75R15 raises the vehicle by 0.30 in (7.5 mm) at the axle (half the +15.0 mm diameter difference).

225/75R15 is 0.59 in taller than 215/75R15 and 10 mm wider, a 2.13% difference in overall diameter.

With the speedometer calibrated for 215/75R15, an indicated 60 mph is actually 61.3 mph on 225/75R15, and revolutions per mile change from 728 to 713.

Both sizes mount on 15-inch wheels.

Size pages

Other comparisons with 215/75R15

Other comparisons with 225/75R15

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