Tire Size Box

265/50R16 vs 265/55R16

265/55R16 compared with 265/50R16

+3.9% diameter, 0.0" width

265/55R16 is 27.48" tall vs 26.43". More than the 3% rule of thumb, so check carefully before switching.

26.4"16" rim5.2"10.4" wide
265/50R16 (solid) compared with 265/55R16 (dashed outline), drawn to scale

With 265/55R16 tires, when your speedometer says 60 mph you are really going

62.4 mph

265/55R16 is +1.04 inches (+3.9%) in overall diameter. That is more than the 3% most shops and makers recommend.

265/50R16265/55R16Difference%
Overall diameter26.43"27.48"+1.04"+3.9%
Section width10.43"10.43"0.00"0.0%
Sidewall height5.22"5.74"+0.52"+10.0%
Circumference83.04"86.32"+3.28"+3.9%
Revolutions per mile763.0734.0−29.0−3.8%

Speedometer difference

If your vehicle came with 265/50R16 and you fit 265/55R16, 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 mph62.4 mph+2.4 mph
65 mph67.6 mph+2.6 mph
70 mph72.8 mph+2.8 mph
75 mph78.0 mph+3.0 mph
80 mph83.2 mph+3.2 mph

Each size on its own

Questions

Which is bigger, 265/50R16 or 265/55R16?
265/55R16 is taller by 1.04 inches (27.48" vs 26.43"). 265/50R16 is the same width.
Can I replace 265/50R16 with 265/55R16?
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 265/55R16 change my speedometer?
When your speedometer reads 60 mph with 265/55R16 fitted (calibrated for 265/50R16), your real speed is 62.4 mph. Your odometer will under-count miles by about 3.9%.
Will 265/55R16 lift my vehicle?
Ride height changes by half the diameter difference: +0.52 inches of ground clearance at the axle.

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