Tire Size Box

235/50R16 vs 235/55R16

235/55R16 compared with 235/50R16

+3.7% diameter, 0.0" width

235/55R16 is 26.18" tall vs 25.25". More than the 3% rule of thumb, so check carefully before switching.

25.3"16" rim4.6"9.3" wide
235/50R16 (solid) compared with 235/55R16 (dashed outline), drawn to scale

With 235/55R16 tires, when your speedometer says 60 mph you are really going

62.2 mph

235/55R16 is +0.93 inches (+3.7%) in overall diameter. That is more than the 3% most shops and makers recommend.

235/50R16235/55R16Difference%
Overall diameter25.25"26.18"+0.93"+3.7%
Section width9.25"9.25"0.00"0.0%
Sidewall height4.63"5.09"+0.46"+10.0%
Circumference79.33"82.24"+2.91"+3.7%
Revolutions per mile798.7770.4−28.2−3.5%

Speedometer difference

If your vehicle came with 235/50R16 and you fit 235/55R16, 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 mph77.7 mph+2.7 mph
80 mph82.9 mph+2.9 mph

Each size on its own

Questions

Which is bigger, 235/50R16 or 235/55R16?
235/55R16 is taller by 0.93 inches (26.18" vs 25.25"). 235/50R16 is the same width.
Can I replace 235/50R16 with 235/55R16?
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 235/55R16 change my speedometer?
When your speedometer reads 60 mph with 235/55R16 fitted (calibrated for 235/50R16), your real speed is 62.2 mph. Your odometer will under-count miles by about 3.7%.
Will 235/55R16 lift my vehicle?
Ride height changes by half the diameter difference: +0.46 inches of ground clearance at the axle.

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