255/55R20 vs 265/45R22

265/45R22 is 0.35 in (8.8 mm) taller than 255/55R20, a +1.12% diameter difference. With the speedometer set for 255/55R20, an indicated 60 mph is 60.7 mph on 265/45R22.

Is this a safe swap?

Diameter difference +1.12%: within the ±3% guideline

By overall diameter alone, 265/45R22 falls inside the ±3% range commonly used as a guideline when replacing 255/55R20. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 255/55R20 (31.04 in) vs 265/45R22 (31.39 in)255/55R2031.04 in × 10.04 in265/45R2231.39 in × 10.43 in
Side profile and tread width, drawn to the same scale.
255/55R20 vs 265/45R22 differences
Measurement255/55R20265/45R22Difference% diff
Overall diameter31.04 in (788.5 mm)31.39 in (797.3 mm)+0.35 in (+8.8 mm)+1.12%
Sidewall height5.52 in (140.3 mm)4.69 in (119.3 mm)−0.83 in (−21.0 mm)−14.97%
Section width10.04 in (255.0 mm)10.43 in (265.0 mm)+0.39 in (+10.0 mm)+3.92%
Circumference97.53 in (2,477.1 mm)98.61 in (2,504.8 mm)+1.09 in (+27.6 mm)+1.12%
Revolutions per mile650643−7−1.10%
True speed with the speedometer calibrated for 255/55R20
IndicatedActual on 255/55R20Actual on 265/45R22Difference
30 mph30.0 mph30.3 mph+0.3 mph
60 mph60.0 mph60.7 mph+0.7 mph
75 mph75.0 mph75.8 mph+0.8 mph

Ride-height change: 265/45R22 raises the vehicle by 0.17 in (4.4 mm) at the axle (half the +8.8 mm diameter difference).

265/45R22 is 0.35 in taller than 255/55R20 and 10 mm wider, a 1.12% difference in overall diameter.

With the speedometer calibrated for 255/55R20, an indicated 60 mph is actually 60.7 mph on 265/45R22, and revolutions per mile change from 650 to 643.

265/45R22 mounts on a 22-inch wheel, a plus-2 fitment from the 20-inch wheel of 255/55R20.

Size pages

Other comparisons with 255/55R20

Other comparisons with 265/45R22

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