TireSizesFinder

205/70R15 vs 235/50R17

235/50R17 is 0.05 in (1.2 mm) shorter than 205/70R15, a −0.18% diameter difference. With the speedometer set for 205/70R15, an indicated 60 mph is 59.9 mph on 235/50R17.

Is this a safe swap?

Diameter difference −0.18%: under 1%

By overall diameter alone, 235/50R17 is a near match for 205/70R15; 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: 205/70R15 (26.30 in) vs 235/50R17 (26.25 in)205/70R1526.30 in × 8.07 in235/50R1726.25 in × 9.25 in
Side profile and tread width, drawn to the same scale.
205/70R15 vs 235/50R17 differences
Measurement205/70R15235/50R17Difference% diff
Overall diameter26.30 in (668.0 mm)26.25 in (666.8 mm)−0.05 in (−1.2 mm)−0.18%
Sidewall height5.65 in (143.5 mm)4.63 in (117.5 mm)−1.02 in (−26.0 mm)−18.12%
Section width8.07 in (205.0 mm)9.25 in (235.0 mm)+1.18 in (+30.0 mm)+14.63%
Circumference82.62 in (2,098.6 mm)82.47 in (2,094.8 mm)−0.15 in (−3.8 mm)−0.18%
Revolutions per mile767768+1+0.18%
True speed with the speedometer calibrated for 205/70R15
IndicatedActual on 205/70R15Actual on 235/50R17Difference
30 mph30.0 mph29.9 mph−0.1 mph
60 mph60.0 mph59.9 mph−0.1 mph
75 mph75.0 mph74.9 mph−0.1 mph

Ride-height change: 235/50R17 lowers the vehicle by 0.02 in (0.6 mm) at the axle (half the −1.2 mm diameter difference).

235/50R17 is 0.05 in shorter than 205/70R15 and 30 mm wider, a 0.18% difference in overall diameter.

With the speedometer calibrated for 205/70R15, an indicated 60 mph is actually 59.9 mph on 235/50R17, and revolutions per mile change from 767 to 768.

235/50R17 mounts on a 17-inch wheel, a plus-2 fitment from the 15-inch wheel of 205/70R15.

Size pages

Other comparisons with 205/70R15

Other comparisons with 235/50R17

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