285/50R22 vs 305/35R24

305/35R24 is 0.81 in (20.7 mm) shorter than 285/50R22, a −2.45% diameter difference. With the speedometer set for 285/50R22, an indicated 60 mph is 58.5 mph on 305/35R24.

Is this a safe swap?

Diameter difference −2.45%: within the ±3% guideline

By overall diameter alone, 305/35R24 falls inside the ±3% range commonly used as a guideline when replacing 285/50R22. 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.

285/50R22 vs 305/35R24 differences
Measurement	285/50R22	305/35R24	Difference	% diff
Overall diameter	33.22 in (843.8 mm)	32.41 in (823.1 mm)	−0.81 in (−20.7 mm)	−2.45%
Sidewall height	5.61 in (142.5 mm)	4.20 in (106.8 mm)	−1.41 in (−35.7 mm)	−25.09%
Section width	11.22 in (285.0 mm)	12.01 in (305.0 mm)	+0.79 in (+20.0 mm)	+7.02%
Circumference	104.37 in (2,650.9 mm)	101.80 in (2,585.8 mm)	−2.56 in (−65.0 mm)	−2.45%
Revolutions per mile	607	622	+15	+2.51%

True speed with the speedometer calibrated for 285/50R22
Indicated	Actual on 285/50R22	Actual on 305/35R24	Difference
30 mph	30.0 mph	29.3 mph	−0.7 mph
60 mph	60.0 mph	58.5 mph	−1.5 mph
75 mph	75.0 mph	73.2 mph	−1.8 mph

Ride-height change: 305/35R24 lowers the vehicle by 0.41 in (10.4 mm) at the axle (half the −20.7 mm diameter difference).

305/35R24 is 0.81 in shorter than 285/50R22 and 20 mm wider, a 2.45% difference in overall diameter.

With the speedometer calibrated for 285/50R22, an indicated 60 mph is actually 58.5 mph on 305/35R24, and revolutions per mile change from 607 to 622.

305/35R24 mounts on a 24-inch wheel, a plus-2 fitment from the 22-inch wheel of 285/50R22.

Size pages

Other comparisons with 285/50R22

Other comparisons with 305/35R24

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