Tire Size Box

225/45R16 vs 225/50R16

225/50R16 compared with 225/45R16

+3.7% diameter, 0.0" width

225/50R16 is 24.86" tall vs 23.97". More than the 3% rule of thumb, so check carefully before switching.

24.0"16" rim4.0"8.9" wide
225/45R16 (solid) compared with 225/50R16 (dashed outline), drawn to scale

With 225/50R16 tires, when your speedometer says 60 mph you are really going

62.2 mph

225/50R16 is +0.89 inches (+3.7%) in overall diameter. That is more than the 3% most shops and makers recommend.

225/45R16225/50R16Difference%
Overall diameter23.97"24.86"+0.89"+3.7%
Section width8.86"8.86"0.00"0.0%
Sidewall height3.99"4.43"+0.44"+11.1%
Circumference75.31"78.09"+2.78"+3.7%
Revolutions per mile841.3811.3−30.0−3.6%

Speedometer difference

If your vehicle came with 225/45R16 and you fit 225/50R16, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.7 mph+0.7 mph
30 mph31.1 mph+1.1 mph
40 mph41.5 mph+1.5 mph
50 mph51.8 mph+1.8 mph
60 mph62.2 mph+2.2 mph
65 mph67.4 mph+2.4 mph
70 mph72.6 mph+2.6 mph
75 mph77.8 mph+2.8 mph
80 mph83.0 mph+3.0 mph

Each size on its own

Questions

Which is bigger, 225/45R16 or 225/50R16?
225/50R16 is taller by 0.89 inches (24.86" vs 23.97"). 225/45R16 is the same width.
Can I replace 225/45R16 with 225/50R16?
It is not recommended without checking carefully. The diameter difference is +3.7%, 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 225/50R16 change my speedometer?
When your speedometer reads 60 mph with 225/50R16 fitted (calibrated for 225/45R16), your real speed is 62.2 mph. Your odometer will under-count miles by about 3.7%.
Will 225/50R16 lift my vehicle?
Ride height changes by half the diameter difference: +0.44 inches of ground clearance at the axle.

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