Tire Size Box

205/50R16 vs 205/55R16

205/55R16 compared with 205/50R16

+3.4% diameter, 0.0" width

205/55R16 is 24.88" tall vs 24.07". More than the 3% rule of thumb, so check carefully before switching.

24.1"16" rim4.0"8.1" wide
205/50R16 (solid) compared with 205/55R16 (dashed outline), drawn to scale

With 205/55R16 tires, when your speedometer says 60 mph you are really going

62.0 mph

205/55R16 is +0.81 inches (+3.4%) in overall diameter. That is more than the 3% most shops and makers recommend.

205/50R16205/55R16Difference%
Overall diameter24.07"24.88"+0.81"+3.4%
Section width8.07"8.07"0.00"0.0%
Sidewall height4.04"4.44"+0.40"+10.0%
Circumference75.62"78.16"+2.54"+3.4%
Revolutions per mile837.9810.7−27.2−3.2%

Speedometer difference

If your vehicle came with 205/50R16 and you fit 205/55R16, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.7 mph+0.7 mph
30 mph31.0 mph+1.0 mph
40 mph41.3 mph+1.3 mph
50 mph51.7 mph+1.7 mph
60 mph62.0 mph+2.0 mph
65 mph67.2 mph+2.2 mph
70 mph72.3 mph+2.3 mph
75 mph77.5 mph+2.5 mph
80 mph82.7 mph+2.7 mph

Each size on its own

Questions

Which is bigger, 205/50R16 or 205/55R16?
205/55R16 is taller by 0.81 inches (24.88" vs 24.07"). 205/50R16 is the same width.
Can I replace 205/50R16 with 205/55R16?
It is not recommended without checking carefully. The diameter difference is +3.4%, 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 205/55R16 change my speedometer?
When your speedometer reads 60 mph with 205/55R16 fitted (calibrated for 205/50R16), your real speed is 62.0 mph. Your odometer will under-count miles by about 3.4%.
Will 205/55R16 lift my vehicle?
Ride height changes by half the diameter difference: +0.40 inches of ground clearance at the axle.

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