255/65R17 vs 225/75R17

225/75R17 is 0.24 in (6.0 mm) taller than 255/65R17, a +0.79% diameter difference. With the speedometer set for 255/65R17, an indicated 60 mph is 60.5 mph on 225/75R17.

Is this a safe swap?

Diameter difference +0.79%: under 1%

By overall diameter alone, 225/75R17 is a near match for 255/65R17; the speedometer changes by less than 1%. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 255/65R17 (30.05 in) vs 225/75R17 (30.29 in)255/65R1730.05 in × 10.04 in225/75R1730.29 in × 8.86 in
Side profile and tread width, drawn to the same scale.
255/65R17 vs 225/75R17 differences
Measurement255/65R17225/75R17Difference% diff
Overall diameter30.05 in (763.3 mm)30.29 in (769.3 mm)+0.24 in (+6.0 mm)+0.79%
Sidewall height6.53 in (165.8 mm)6.64 in (168.8 mm)+0.12 in (+3.0 mm)+1.81%
Section width10.04 in (255.0 mm)8.86 in (225.0 mm)−1.18 in (−30.0 mm)−11.76%
Circumference94.41 in (2,398.0 mm)95.15 in (2,416.8 mm)+0.74 in (+18.8 mm)+0.79%
Revolutions per mile671666−5−0.78%
True speed with the speedometer calibrated for 255/65R17
IndicatedActual on 255/65R17Actual on 225/75R17Difference
30 mph30.0 mph30.2 mph+0.2 mph
60 mph60.0 mph60.5 mph+0.5 mph
75 mph75.0 mph75.6 mph+0.6 mph

Ride-height change: 225/75R17 raises the vehicle by 0.12 in (3.0 mm) at the axle (half the +6.0 mm diameter difference).

225/75R17 is 0.24 in taller than 255/65R17 and 30 mm narrower, a 0.79% difference in overall diameter.

With the speedometer calibrated for 255/65R17, an indicated 60 mph is actually 60.5 mph on 225/75R17, and revolutions per mile change from 671 to 666.

Both sizes mount on 17-inch wheels.

Size pages

Other comparisons with 255/65R17

Other comparisons with 225/75R17

Source: Calculated from standard tire geometry formulas. Verified . How these numbers are calculated.