245/35R19 vs 255/35R19

255/35R19 is 0.28 in (7.0 mm) taller than 245/35R19, a +1.07% diameter difference. With the speedometer set for 245/35R19, an indicated 60 mph is 60.6 mph on 255/35R19.

Is this a safe swap?

Diameter difference +1.07%: within the ±3% guideline

By overall diameter alone, 255/35R19 falls inside the ±3% range commonly used as a guideline when replacing 245/35R19. 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.

245/35R19 vs 255/35R19 differences
Measurement	245/35R19	255/35R19	Difference	% diff
Overall diameter	25.75 in (654.1 mm)	26.03 in (661.1 mm)	+0.28 in (+7.0 mm)	+1.07%
Sidewall height	3.38 in (85.8 mm)	3.51 in (89.3 mm)	+0.14 in (+3.5 mm)	+4.08%
Section width	9.65 in (245.0 mm)	10.04 in (255.0 mm)	+0.39 in (+10.0 mm)	+4.08%
Circumference	80.90 in (2,054.9 mm)	81.77 in (2,076.9 mm)	+0.87 in (+22.0 mm)	+1.07%
Revolutions per mile	783	775	−8	−1.06%

True speed with the speedometer calibrated for 245/35R19
Indicated	Actual on 245/35R19	Actual on 255/35R19	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	75.8 mph	+0.8 mph

Ride-height change: 255/35R19 raises the vehicle by 0.14 in (3.5 mm) at the axle (half the +7.0 mm diameter difference).

255/35R19 is 0.28 in taller than 245/35R19 and 10 mm wider, a 1.07% difference in overall diameter.

With the speedometer calibrated for 245/35R19, an indicated 60 mph is actually 60.6 mph on 255/35R19, and revolutions per mile change from 783 to 775.

Both sizes mount on 19-inch wheels.

Size pages

Other comparisons with 245/35R19

Other comparisons with 255/35R19

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