TireSizesFinder

225/50R15 vs 215/40R17

215/40R17 is 0.09 in (2.2 mm) shorter than 225/50R15, a −0.36% diameter difference. With the speedometer set for 225/50R15, an indicated 60 mph is 59.8 mph on 215/40R17.

Is this a safe swap?

Diameter difference −0.36%: under 1%

By overall diameter alone, 215/40R17 is a near match for 225/50R15; 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: 225/50R15 (23.86 in) vs 215/40R17 (23.77 in)225/50R1523.86 in × 8.86 in215/40R1723.77 in × 8.46 in
Side profile and tread width, drawn to the same scale.
225/50R15 vs 215/40R17 differences
Measurement225/50R15215/40R17Difference% diff
Overall diameter23.86 in (606.0 mm)23.77 in (603.8 mm)−0.09 in (−2.2 mm)−0.36%
Sidewall height4.43 in (112.5 mm)3.39 in (86.0 mm)−1.04 in (−26.5 mm)−23.56%
Section width8.86 in (225.0 mm)8.46 in (215.0 mm)−0.39 in (−10.0 mm)−4.44%
Circumference74.95 in (1,903.8 mm)74.68 in (1,896.9 mm)−0.27 in (−6.9 mm)−0.36%
Revolutions per mile845848+3+0.36%
True speed with the speedometer calibrated for 225/50R15
IndicatedActual on 225/50R15Actual on 215/40R17Difference
30 mph30.0 mph29.9 mph−0.1 mph
60 mph60.0 mph59.8 mph−0.2 mph
75 mph75.0 mph74.7 mph−0.3 mph

Ride-height change: 215/40R17 lowers the vehicle by 0.04 in (1.1 mm) at the axle (half the −2.2 mm diameter difference).

215/40R17 is 0.09 in shorter than 225/50R15 and 10 mm narrower, a 0.36% difference in overall diameter.

With the speedometer calibrated for 225/50R15, an indicated 60 mph is actually 59.8 mph on 215/40R17, and revolutions per mile change from 845 to 848.

215/40R17 mounts on a 17-inch wheel, a plus-2 fitment from the 15-inch wheel of 225/50R15.

Size pages

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