Tire Size Box

245/45R16 vs 245/50R16

245/50R16 compared with 245/45R16

+3.9% diameter, 0.0" width

245/50R16 is 25.65" tall vs 24.68". More than the 3% rule of thumb, so check carefully before switching.

24.7"16" rim4.3"9.6" wide
245/45R16 (solid) compared with 245/50R16 (dashed outline), drawn to scale

With 245/50R16 tires, when your speedometer says 60 mph you are really going

62.3 mph

245/50R16 is +0.96 inches (+3.9%) in overall diameter. That is more than the 3% most shops and makers recommend.

245/45R16245/50R16Difference%
Overall diameter24.68"25.65"+0.96"+3.9%
Section width9.65"9.65"0.00"0.0%
Sidewall height4.34"4.82"+0.48"+11.1%
Circumference77.54"80.57"+3.03"+3.9%
Revolutions per mile817.1786.4−30.7−3.8%

Speedometer difference

If your vehicle came with 245/45R16 and you fit 245/50R16, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.8 mph+0.8 mph
30 mph31.2 mph+1.2 mph
40 mph41.6 mph+1.6 mph
50 mph52.0 mph+2.0 mph
60 mph62.3 mph+2.3 mph
65 mph67.5 mph+2.5 mph
70 mph72.7 mph+2.7 mph
75 mph77.9 mph+2.9 mph
80 mph83.1 mph+3.1 mph

Each size on its own

Questions

Which is bigger, 245/45R16 or 245/50R16?
245/50R16 is taller by 0.96 inches (25.65" vs 24.68"). 245/45R16 is the same width.
Can I replace 245/45R16 with 245/50R16?
It is not recommended without checking carefully. The diameter difference is +3.9%, 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 245/50R16 change my speedometer?
When your speedometer reads 60 mph with 245/50R16 fitted (calibrated for 245/45R16), your real speed is 62.3 mph. Your odometer will under-count miles by about 3.9%.
Will 245/50R16 lift my vehicle?
Ride height changes by half the diameter difference: +0.48 inches of ground clearance at the axle.

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