235/50R19 vs 265/35R21

265/35R21 is 0.05 in (1.3 mm) taller than 235/50R19, a +0.18% diameter difference. With the speedometer set for 235/50R19, an indicated 60 mph is 60.1 mph on 265/35R21.

Is this a safe swap?

Diameter difference +0.18%: under 1%

By overall diameter alone, 265/35R21 is a near match for 235/50R19; 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.

235/50R19 vs 265/35R21 differences
Measurement	235/50R19	265/35R21	Difference	% diff
Overall diameter	28.25 in (717.6 mm)	28.30 in (718.9 mm)	+0.05 in (+1.3 mm)	+0.18%
Sidewall height	4.63 in (117.5 mm)	3.65 in (92.8 mm)	−0.97 in (−24.7 mm)	−21.06%
Section width	9.25 in (235.0 mm)	10.43 in (265.0 mm)	+1.18 in (+30.0 mm)	+12.77%
Circumference	88.76 in (2,254.4 mm)	88.92 in (2,258.5 mm)	+0.16 in (+4.1 mm)	+0.18%
Revolutions per mile	714	713	−1	−0.18%

True speed with the speedometer calibrated for 235/50R19
Indicated	Actual on 235/50R19	Actual on 265/35R21	Difference
30 mph	30.0 mph	30.1 mph	+0.1 mph
60 mph	60.0 mph	60.1 mph	+0.1 mph
75 mph	75.0 mph	75.1 mph	+0.1 mph

Ride-height change: 265/35R21 raises the vehicle by 0.03 in (0.7 mm) at the axle (half the +1.3 mm diameter difference).

265/35R21 is 0.05 in taller than 235/50R19 and 30 mm wider, a 0.18% difference in overall diameter.

With the speedometer calibrated for 235/50R19, an indicated 60 mph is actually 60.1 mph on 265/35R21, and revolutions per mile change from 714 to 713.

265/35R21 mounts on a 21-inch wheel, a plus-2 fitment from the 19-inch wheel of 235/50R19.

Size pages

Other comparisons with 235/50R19

Other comparisons with 265/35R21

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