33x12.50R22 vs 325/45R22

325/45R22 is 0.52 in (13.1 mm) taller than 33x12.50R22, a +1.56% diameter difference. With the speedometer set for 33x12.50R22, an indicated 60 mph is 60.9 mph on 325/45R22.

Is this a safe swap?

Diameter difference +1.56%: within the ±3% guideline

By overall diameter alone, 325/45R22 falls inside the ±3% range commonly used as a guideline when replacing 33x12.50R22. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 33x12.50R22 (33.00 in) vs 325/45R22 (33.52 in)33x12.50R2233.00 in × 12.50 in325/45R2233.52 in × 12.80 in
Side profile and tread width, drawn to the same scale.
33x12.50R22 vs 325/45R22 differences
Measurement33x12.50R22325/45R22Difference% diff
Overall diameter33.00 in (838.2 mm)33.52 in (851.3 mm)+0.52 in (+13.1 mm)+1.56%
Sidewall height5.50 in (139.7 mm)5.76 in (146.3 mm)+0.26 in (+6.6 mm)+4.69%
Section width12.50 in (317.5 mm)12.80 in (325.0 mm)+0.30 in (+7.5 mm)+2.36%
Circumference103.67 in (2,633.3 mm)105.29 in (2,674.4 mm)+1.62 in (+41.2 mm)+1.56%
Revolutions per mile611602−9−1.54%
True speed with the speedometer calibrated for 33x12.50R22
IndicatedActual on 33x12.50R22Actual on 325/45R22Difference
30 mph30.0 mph30.5 mph+0.5 mph
60 mph60.0 mph60.9 mph+0.9 mph
75 mph75.0 mph76.2 mph+1.2 mph

Ride-height change: 325/45R22 raises the vehicle by 0.26 in (6.6 mm) at the axle (half the +13.1 mm diameter difference).

325/45R22 is 0.52 in taller than 33x12.50R22 and 8 mm wider, a 1.56% difference in overall diameter.

With the speedometer calibrated for 33x12.50R22, an indicated 60 mph is actually 60.9 mph on 325/45R22, and revolutions per mile change from 611 to 602.

Both sizes mount on 22-inch wheels.

Size pages

Other comparisons with 33x12.50R22

Other comparisons with 325/45R22

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