245/60R18 vs 275/50R19

275/50R19 is 0.25 in (6.4 mm) taller than 245/60R18, a +0.85% diameter difference. With the speedometer set for 245/60R18, an indicated 60 mph is 60.5 mph on 275/50R19.

Is this a safe swap?

Diameter difference +0.85%: under 1%

By overall diameter alone, 275/50R19 is a near match for 245/60R18; 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.

245/60R18 vs 275/50R19 differences
Measurement	245/60R18	275/50R19	Difference	% diff
Overall diameter	29.57 in (751.2 mm)	29.83 in (757.6 mm)	+0.25 in (+6.4 mm)	+0.85%
Sidewall height	5.79 in (147.0 mm)	5.41 in (137.5 mm)	−0.37 in (−9.5 mm)	−6.46%
Section width	9.65 in (245.0 mm)	10.83 in (275.0 mm)	+1.18 in (+30.0 mm)	+12.24%
Circumference	92.91 in (2,360.0 mm)	93.70 in (2,380.1 mm)	+0.79 in (+20.1 mm)	+0.85%
Revolutions per mile	682	676	−6	−0.84%

True speed with the speedometer calibrated for 245/60R18
Indicated	Actual on 245/60R18	Actual on 275/50R19	Difference
30 mph	30.0 mph	30.3 mph	+0.3 mph
60 mph	60.0 mph	60.5 mph	+0.5 mph
75 mph	75.0 mph	75.6 mph	+0.6 mph

Ride-height change: 275/50R19 raises the vehicle by 0.13 in (3.2 mm) at the axle (half the +6.4 mm diameter difference).

275/50R19 is 0.25 in taller than 245/60R18 and 30 mm wider, a 0.85% difference in overall diameter.

With the speedometer calibrated for 245/60R18, an indicated 60 mph is actually 60.5 mph on 275/50R19, and revolutions per mile change from 682 to 676.

275/50R19 mounts on a 19-inch wheel, a plus-1 fitment from the 18-inch wheel of 245/60R18.

Size pages

Other comparisons with 245/60R18

Other comparisons with 275/50R19

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