Tire Size Box

325/45R19 vs 325/50R19

325/50R19 compared with 325/45R19

+4.2% diameter, 0.0" width

325/50R19 is 31.80" tall vs 30.52". More than the 3% rule of thumb, so check carefully before switching.

30.5"19" rim5.8"12.8" wide
325/45R19 (solid) compared with 325/50R19 (dashed outline), drawn to scale

With 325/50R19 tires, when your speedometer says 60 mph you are really going

62.5 mph

325/50R19 is +1.28 inches (+4.2%) in overall diameter. That is more than the 3% most shops and makers recommend.

325/45R19325/50R19Difference%
Overall diameter30.52"31.80"+1.28"+4.2%
Section width12.80"12.80"0.00"0.0%
Sidewall height5.76"6.40"+0.64"+11.1%
Circumference95.87"99.89"+4.02"+4.2%
Revolutions per mile660.9634.3−26.6−4.0%

Speedometer difference

If your vehicle came with 325/45R19 and you fit 325/50R19, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.8 mph+0.8 mph
30 mph31.3 mph+1.3 mph
40 mph41.7 mph+1.7 mph
50 mph52.1 mph+2.1 mph
60 mph62.5 mph+2.5 mph
65 mph67.7 mph+2.7 mph
70 mph72.9 mph+2.9 mph
75 mph78.1 mph+3.1 mph
80 mph83.4 mph+3.4 mph

Each size on its own

Questions

Which is bigger, 325/45R19 or 325/50R19?
325/50R19 is taller by 1.28 inches (31.80" vs 30.52"). 325/45R19 is the same width.
Can I replace 325/45R19 with 325/50R19?
It is not recommended without checking carefully. The diameter difference is +4.2%, 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 325/50R19 change my speedometer?
When your speedometer reads 60 mph with 325/50R19 fitted (calibrated for 325/45R19), your real speed is 62.5 mph. Your odometer will under-count miles by about 4.2%.
Will 325/50R19 lift my vehicle?
Ride height changes by half the diameter difference: +0.64 inches of ground clearance at the axle.

Other comparisons