215/65R15 vs 235/50R17

235/50R17 is 0.25 in (6.3 mm) taller than 215/65R15, a +0.95% diameter difference. With the speedometer set for 215/65R15, an indicated 60 mph is 60.6 mph on 235/50R17.

Is this a safe swap?

Diameter difference +0.95%: under 1%

By overall diameter alone, 235/50R17 is a near match for 215/65R15; 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.

215/65R15 vs 235/50R17 differences
Measurement	215/65R15	235/50R17	Difference	% diff
Overall diameter	26.00 in (660.5 mm)	26.25 in (666.8 mm)	+0.25 in (+6.3 mm)	+0.95%
Sidewall height	5.50 in (139.8 mm)	4.63 in (117.5 mm)	−0.88 in (−22.2 mm)	−15.92%
Section width	8.46 in (215.0 mm)	9.25 in (235.0 mm)	+0.79 in (+20.0 mm)	+9.30%
Circumference	81.69 in (2,075.0 mm)	82.47 in (2,094.8 mm)	+0.78 in (+19.8 mm)	+0.95%
Revolutions per mile	776	768	−7	−0.94%

True speed with the speedometer calibrated for 215/65R15
Indicated	Actual on 215/65R15	Actual on 235/50R17	Difference
30 mph	30.0 mph	30.3 mph	+0.3 mph
60 mph	60.0 mph	60.6 mph	+0.6 mph
75 mph	75.0 mph	75.7 mph	+0.7 mph

Ride-height change: 235/50R17 raises the vehicle by 0.12 in (3.1 mm) at the axle (half the +6.3 mm diameter difference).

235/50R17 is 0.25 in taller than 215/65R15 and 20 mm wider, a 0.95% difference in overall diameter.

With the speedometer calibrated for 215/65R15, an indicated 60 mph is actually 60.6 mph on 235/50R17, and revolutions per mile change from 776 to 768.

235/50R17 mounts on a 17-inch wheel, a plus-2 fitment from the 15-inch wheel of 215/65R15.

Size pages

Other comparisons with 215/65R15

Other comparisons with 235/50R17

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