235/45R18 vs 265/35R19

265/35R19 is 0.02 in (0.6 mm) shorter than 235/45R18, a −0.09% diameter difference. With the speedometer set for 235/45R18, an indicated 60 mph is 59.9 mph on 265/35R19.

Is this a safe swap?

Diameter difference −0.09%: under 1%

By overall diameter alone, 265/35R19 is a near match for 235/45R18; 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: 235/45R18 (26.33 in) vs 265/35R19 (26.30 in)235/45R1826.33 in × 9.25 in265/35R1926.30 in × 10.43 in
Side profile and tread width, drawn to the same scale.
235/45R18 vs 265/35R19 differences
Measurement235/45R18265/35R19Difference% diff
Overall diameter26.33 in (668.7 mm)26.30 in (668.1 mm)−0.02 in (−0.6 mm)−0.09%
Sidewall height4.16 in (105.8 mm)3.65 in (92.8 mm)−0.51 in (−13.0 mm)−12.29%
Section width9.25 in (235.0 mm)10.43 in (265.0 mm)+1.18 in (+30.0 mm)+12.77%
Circumference82.71 in (2,100.8 mm)82.63 in (2,098.9 mm)−0.07 in (−1.9 mm)−0.09%
Revolutions per mile766767+1+0.09%
True speed with the speedometer calibrated for 235/45R18
IndicatedActual on 235/45R18Actual on 265/35R19Difference
30 mph30.0 mph30.0 mph0.0 mph
60 mph60.0 mph59.9 mph−0.1 mph
75 mph75.0 mph74.9 mph−0.1 mph

Ride-height change: 265/35R19 lowers the vehicle by 0.01 in (0.3 mm) at the axle (half the −0.6 mm diameter difference).

265/35R19 is 0.02 in shorter than 235/45R18 and 30 mm wider, a 0.09% difference in overall diameter.

With the speedometer calibrated for 235/45R18, an indicated 60 mph is actually 59.9 mph on 265/35R19, and revolutions per mile change from 766 to 767.

265/35R19 mounts on a 19-inch wheel, a plus-1 fitment from the 18-inch wheel of 235/45R18.

Size pages

Other comparisons with 235/45R18

Other comparisons with 265/35R19

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