295/35R20 vs 255/30R22

255/30R22 is 0.11 in (2.7 mm) shorter than 295/35R20, a −0.38% diameter difference. With the speedometer set for 295/35R20, an indicated 60 mph is 59.8 mph on 255/30R22.

Is this a safe swap?

Diameter difference −0.38%: under 1%

By overall diameter alone, 255/30R22 is a near match for 295/35R20; 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.

295/35R20 vs 255/30R22 differences
Measurement	295/35R20	255/30R22	Difference	% diff
Overall diameter	28.13 in (714.5 mm)	28.02 in (711.8 mm)	−0.11 in (−2.7 mm)	−0.38%
Sidewall height	4.06 in (103.3 mm)	3.01 in (76.5 mm)	−1.05 in (−26.7 mm)	−25.91%
Section width	11.61 in (295.0 mm)	10.04 in (255.0 mm)	−1.57 in (−40.0 mm)	−13.56%
Circumference	88.37 in (2,244.7 mm)	88.04 in (2,236.2 mm)	−0.33 in (−8.5 mm)	−0.38%
Revolutions per mile	717	720	+3	+0.38%

True speed with the speedometer calibrated for 295/35R20
Indicated	Actual on 295/35R20	Actual on 255/30R22	Difference
30 mph	30.0 mph	29.9 mph	−0.1 mph
60 mph	60.0 mph	59.8 mph	−0.2 mph
75 mph	75.0 mph	74.7 mph	−0.3 mph

Ride-height change: 255/30R22 lowers the vehicle by 0.05 in (1.4 mm) at the axle (half the −2.7 mm diameter difference).

255/30R22 is 0.11 in shorter than 295/35R20 and 40 mm narrower, a 0.38% difference in overall diameter.

With the speedometer calibrated for 295/35R20, an indicated 60 mph is actually 59.8 mph on 255/30R22, and revolutions per mile change from 717 to 720.

255/30R22 mounts on a 22-inch wheel, a plus-2 fitment from the 20-inch wheel of 295/35R20.

Size pages

Other comparisons with 295/35R20

Other comparisons with 255/30R22

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