Tire Size Box

235/45R22 vs 235/50R22

235/50R22 compared with 235/45R22

+3.1% diameter, 0.0" width

235/50R22 is 31.25" tall vs 30.33". More than the 3% rule of thumb, so check carefully before switching.

30.3"22" rim4.2"9.3" wide
235/45R22 (solid) compared with 235/50R22 (dashed outline), drawn to scale

With 235/50R22 tires, when your speedometer says 60 mph you are really going

61.8 mph

235/50R22 is +0.93 inches (+3.1%) in overall diameter. That is more than the 3% most shops and makers recommend.

235/45R22235/50R22Difference%
Overall diameter30.33"31.25"+0.93"+3.1%
Section width9.25"9.25"0.00"0.0%
Sidewall height4.16"4.63"+0.46"+11.1%
Circumference95.27"98.18"+2.91"+3.1%
Revolutions per mile665.0645.3−19.7−3.0%

Speedometer difference

If your vehicle came with 235/45R22 and you fit 235/50R22, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.6 mph+0.6 mph
30 mph30.9 mph+0.9 mph
40 mph41.2 mph+1.2 mph
50 mph51.5 mph+1.5 mph
60 mph61.8 mph+1.8 mph
65 mph67.0 mph+2.0 mph
70 mph72.1 mph+2.1 mph
75 mph77.3 mph+2.3 mph
80 mph82.4 mph+2.4 mph

Each size on its own

Questions

Which is bigger, 235/45R22 or 235/50R22?
235/50R22 is taller by 0.93 inches (31.25" vs 30.33"). 235/45R22 is the same width.
Can I replace 235/45R22 with 235/50R22?
It is not recommended without checking carefully. The diameter difference is +3.1%, more than the 3% most shops and makers allow. It will throw off the speedometer and may affect ABS, stability control and clearance.
How much will 235/50R22 change my speedometer?
When your speedometer reads 60 mph with 235/50R22 fitted (calibrated for 235/45R22), your real speed is 61.8 mph. Your odometer will under-count miles by about 3.1%.
Will 235/50R22 lift my vehicle?
Ride height changes by half the diameter difference: +0.46 inches of ground clearance at the axle.

Other comparisons