295/30R21 vs 295/25R22

295/25R22 is 0.16 in (4.1 mm) shorter than 295/30R21, a −0.58% diameter difference. With the speedometer set for 295/30R21, an indicated 60 mph is 59.7 mph on 295/25R22.

Is this a safe swap?

Diameter difference −0.58%: under 1%

By overall diameter alone, 295/25R22 is a near match for 295/30R21; 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: 295/30R21 (27.97 in) vs 295/25R22 (27.81 in)295/30R2127.97 in × 11.61 in295/25R2227.81 in × 11.61 in
Side profile and tread width, drawn to the same scale.
295/30R21 vs 295/25R22 differences
Measurement295/30R21295/25R22Difference% diff
Overall diameter27.97 in (710.4 mm)27.81 in (706.3 mm)−0.16 in (−4.1 mm)−0.58%
Sidewall height3.48 in (88.5 mm)2.90 in (73.8 mm)−0.58 in (−14.7 mm)−16.67%
Section width11.61 in (295.0 mm)11.61 in (295.0 mm)0.00 in (0.0 mm)0.00%
Circumference87.87 in (2,231.8 mm)87.36 in (2,218.9 mm)−0.51 in (−12.9 mm)−0.58%
Revolutions per mile721725+4+0.58%
True speed with the speedometer calibrated for 295/30R21
IndicatedActual on 295/30R21Actual on 295/25R22Difference
30 mph30.0 mph29.8 mph−0.2 mph
60 mph60.0 mph59.7 mph−0.3 mph
75 mph75.0 mph74.6 mph−0.4 mph

Ride-height change: 295/25R22 lowers the vehicle by 0.08 in (2.1 mm) at the axle (half the −4.1 mm diameter difference).

295/25R22 is 0.16 in shorter than 295/30R21 and the same width, a 0.58% difference in overall diameter.

With the speedometer calibrated for 295/30R21, an indicated 60 mph is actually 59.7 mph on 295/25R22, and revolutions per mile change from 721 to 725.

295/25R22 mounts on a 22-inch wheel, a plus-1 fitment from the 21-inch wheel of 295/30R21.

Size pages

Other comparisons with 295/30R21

Other comparisons with 295/25R22

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