215/45R18 vs 245/35R19

245/35R19 is 0.13 in (3.4 mm) taller than 215/45R18, a +0.52% diameter difference. With the speedometer set for 215/45R18, an indicated 60 mph is 60.3 mph on 245/35R19.

Is this a safe swap?

Diameter difference +0.52%: under 1%

By overall diameter alone, 245/35R19 is a near match for 215/45R18; the speedometer changes by less than 1%. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

Side profile and tread width, drawn to the same scale.

215/45R18 vs 245/35R19 differences
Measurement	215/45R18	245/35R19	Difference	% diff
Overall diameter	25.62 in (650.7 mm)	25.75 in (654.1 mm)	+0.13 in (+3.4 mm)	+0.52%
Sidewall height	3.81 in (96.8 mm)	3.38 in (85.8 mm)	−0.43 in (−11.0 mm)	−11.37%
Section width	8.46 in (215.0 mm)	9.65 in (245.0 mm)	+1.18 in (+30.0 mm)	+13.95%
Circumference	80.48 in (2,044.2 mm)	80.90 in (2,054.9 mm)	+0.42 in (+10.7 mm)	+0.52%
Revolutions per mile	787	783	−4	−0.52%

True speed with the speedometer calibrated for 215/45R18
Indicated	Actual on 215/45R18	Actual on 245/35R19	Difference
30 mph	30.0 mph	30.2 mph	+0.2 mph
60 mph	60.0 mph	60.3 mph	+0.3 mph
75 mph	75.0 mph	75.4 mph	+0.4 mph

Ride-height change: 245/35R19 raises the vehicle by 0.07 in (1.7 mm) at the axle (half the +3.4 mm diameter difference).

245/35R19 is 0.13 in taller than 215/45R18 and 30 mm wider, a 0.52% difference in overall diameter.

With the speedometer calibrated for 215/45R18, an indicated 60 mph is actually 60.3 mph on 245/35R19, and revolutions per mile change from 787 to 783.

245/35R19 mounts on a 19-inch wheel, a plus-1 fitment from the 18-inch wheel of 215/45R18.

Size pages

Other comparisons with 215/45R18

Other comparisons with 245/35R19

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