225/75R15 vs 245/65R16

245/65R16 is 0.25 in (6.4 mm) taller than 225/75R15, a +0.89% diameter difference. With the speedometer set for 225/75R15, an indicated 60 mph is 60.5 mph on 245/65R16.

Is this a safe swap?

Diameter difference +0.89%: under 1%

By overall diameter alone, 245/65R16 is a near match for 225/75R15; the speedometer changes by less than 1%. 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.

225/75R15 vs 245/65R16 differences
Measurement	225/75R15	245/65R16	Difference	% diff
Overall diameter	28.29 in (718.5 mm)	28.54 in (724.9 mm)	+0.25 in (+6.4 mm)	+0.89%
Sidewall height	6.64 in (168.8 mm)	6.27 in (159.3 mm)	−0.37 in (−9.5 mm)	−5.63%
Section width	8.86 in (225.0 mm)	9.65 in (245.0 mm)	+0.79 in (+20.0 mm)	+8.89%
Circumference	88.87 in (2,257.2 mm)	89.66 in (2,277.3 mm)	+0.79 in (+20.1 mm)	+0.89%
Revolutions per mile	713	707	−6	−0.88%

True speed with the speedometer calibrated for 225/75R15
Indicated	Actual on 225/75R15	Actual on 245/65R16	Difference
30 mph	30.0 mph	30.3 mph	+0.3 mph
60 mph	60.0 mph	60.5 mph	+0.5 mph
75 mph	75.0 mph	75.7 mph	+0.7 mph

Ride-height change: 245/65R16 raises the vehicle by 0.13 in (3.2 mm) at the axle (half the +6.4 mm diameter difference).

245/65R16 is 0.25 in taller than 225/75R15 and 20 mm wider, a 0.89% difference in overall diameter.

With the speedometer calibrated for 225/75R15, an indicated 60 mph is actually 60.5 mph on 245/65R16, and revolutions per mile change from 713 to 707.

245/65R16 mounts on a 16-inch wheel, a plus-1 fitment from the 15-inch wheel of 225/75R15.

Size pages

Other comparisons with 225/75R15

Other comparisons with 245/65R16

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