285/45R21 vs 295/40R22

295/40R22 is 0.19 in (4.9 mm) taller than 285/45R21, a +0.62% diameter difference. With the speedometer set for 285/45R21, an indicated 60 mph is 60.4 mph on 295/40R22.

Is this a safe swap?

Diameter difference +0.62%: under 1%

By overall diameter alone, 295/40R22 is a near match for 285/45R21; 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: 285/45R21 (31.10 in) vs 295/40R22 (31.29 in)285/45R2131.10 in × 11.22 in295/40R2231.29 in × 11.61 in
Side profile and tread width, drawn to the same scale.
285/45R21 vs 295/40R22 differences
Measurement285/45R21295/40R22Difference% diff
Overall diameter31.10 in (789.9 mm)31.29 in (794.8 mm)+0.19 in (+4.9 mm)+0.62%
Sidewall height5.05 in (128.3 mm)4.65 in (118.0 mm)−0.40 in (−10.2 mm)−7.99%
Section width11.22 in (285.0 mm)11.61 in (295.0 mm)+0.39 in (+10.0 mm)+3.51%
Circumference97.70 in (2,481.5 mm)98.30 in (2,496.9 mm)+0.61 in (+15.4 mm)+0.62%
Revolutions per mile649645−4−0.62%
True speed with the speedometer calibrated for 285/45R21
IndicatedActual on 285/45R21Actual on 295/40R22Difference
30 mph30.0 mph30.2 mph+0.2 mph
60 mph60.0 mph60.4 mph+0.4 mph
75 mph75.0 mph75.5 mph+0.5 mph

Ride-height change: 295/40R22 raises the vehicle by 0.10 in (2.4 mm) at the axle (half the +4.9 mm diameter difference).

295/40R22 is 0.19 in taller than 285/45R21 and 10 mm wider, a 0.62% difference in overall diameter.

With the speedometer calibrated for 285/45R21, an indicated 60 mph is actually 60.4 mph on 295/40R22, and revolutions per mile change from 649 to 645.

295/40R22 mounts on a 22-inch wheel, a plus-1 fitment from the 21-inch wheel of 285/45R21.

Size pages

Other comparisons with 285/45R21

Other comparisons with 295/40R22

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