275/50R21 vs 265/45R22

265/45R22 is 0.44 in (11.1 mm) shorter than 275/50R21, a −1.37% diameter difference. With the speedometer set for 275/50R21, an indicated 60 mph is 59.2 mph on 265/45R22.

Is this a safe swap?

Diameter difference −1.37%: within the ±3% guideline

By overall diameter alone, 265/45R22 falls inside the ±3% range commonly used as a guideline when replacing 275/50R21. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

Side profile and tread width, drawn to the same scale.

275/50R21 vs 265/45R22 differences
Measurement	275/50R21	265/45R22	Difference	% diff
Overall diameter	31.83 in (808.4 mm)	31.39 in (797.3 mm)	−0.44 in (−11.1 mm)	−1.37%
Sidewall height	5.41 in (137.5 mm)	4.69 in (119.3 mm)	−0.72 in (−18.2 mm)	−13.27%
Section width	10.83 in (275.0 mm)	10.43 in (265.0 mm)	−0.39 in (−10.0 mm)	−3.64%
Circumference	99.99 in (2,539.7 mm)	98.61 in (2,504.8 mm)	−1.37 in (−34.9 mm)	−1.37%
Revolutions per mile	634	643	+9	+1.39%

True speed with the speedometer calibrated for 275/50R21
Indicated	Actual on 275/50R21	Actual on 265/45R22	Difference
30 mph	30.0 mph	29.6 mph	−0.4 mph
60 mph	60.0 mph	59.2 mph	−0.8 mph
75 mph	75.0 mph	74.0 mph	−1.0 mph

Ride-height change: 265/45R22 lowers the vehicle by 0.22 in (5.6 mm) at the axle (half the −11.1 mm diameter difference).

265/45R22 is 0.44 in shorter than 275/50R21 and 10 mm narrower, a 1.37% difference in overall diameter.

With the speedometer calibrated for 275/50R21, an indicated 60 mph is actually 59.2 mph on 265/45R22, and revolutions per mile change from 634 to 643.

265/45R22 mounts on a 22-inch wheel, a plus-1 fitment from the 21-inch wheel of 275/50R21.

Size pages

Other comparisons with 275/50R21

Other comparisons with 265/45R22

Source: Calculated from standard tire geometry formulas. Verified 2026-09-27. How these numbers are calculated.