TireSizesFinder

255/50R21 vs 295/40R22

295/40R22 is 0.25 in (6.4 mm) taller than 255/50R21, a +0.81% diameter difference. With the speedometer set for 255/50R21, an indicated 60 mph is 60.5 mph on 295/40R22.

Is this a safe swap?

Diameter difference +0.81%: under 1%

By overall diameter alone, 295/40R22 is a near match for 255/50R21; the speedometer changes by less than 1%. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 255/50R21 (31.04 in) vs 295/40R22 (31.29 in)255/50R2131.04 in × 10.04 in295/40R2231.29 in × 11.61 in
Side profile and tread width, drawn to the same scale.
255/50R21 vs 295/40R22 differences
Measurement255/50R21295/40R22Difference% diff
Overall diameter31.04 in (788.4 mm)31.29 in (794.8 mm)+0.25 in (+6.4 mm)+0.81%
Sidewall height5.02 in (127.5 mm)4.65 in (118.0 mm)−0.37 in (−9.5 mm)−7.45%
Section width10.04 in (255.0 mm)11.61 in (295.0 mm)+1.57 in (+40.0 mm)+15.69%
Circumference97.51 in (2,476.8 mm)98.30 in (2,496.9 mm)+0.79 in (+20.1 mm)+0.81%
Revolutions per mile650645−5−0.81%
True speed with the speedometer calibrated for 255/50R21
IndicatedActual on 255/50R21Actual on 295/40R22Difference
30 mph30.0 mph30.2 mph+0.2 mph
60 mph60.0 mph60.5 mph+0.5 mph
75 mph75.0 mph75.6 mph+0.6 mph

Ride-height change: 295/40R22 raises the vehicle by 0.13 in (3.2 mm) at the axle (half the +6.4 mm diameter difference).

295/40R22 is 0.25 in taller than 255/50R21 and 40 mm wider, a 0.81% difference in overall diameter.

With the speedometer calibrated for 255/50R21, an indicated 60 mph is actually 60.5 mph on 295/40R22, and revolutions per mile change from 650 to 645.

295/40R22 mounts on a 22-inch wheel, a plus-1 fitment from the 21-inch wheel of 255/50R21.

Size pages

Other comparisons with 255/50R21

Other comparisons with 295/40R22

Source: Calculated from standard tire geometry formulas. Verified . How these numbers are calculated.