Tire Size Box

215/50R17 vs 215/55R17

215/55R17 compared with 215/50R17

+3.3% diameter, 0.0" width

215/55R17 is 26.31" tall vs 25.46". More than the 3% rule of thumb, so check carefully before switching.

25.5"17" rim4.2"8.5" wide
215/50R17 (solid) compared with 215/55R17 (dashed outline), drawn to scale

With 215/55R17 tires, when your speedometer says 60 mph you are really going

62.0 mph

215/55R17 is +0.85 inches (+3.3%) in overall diameter. That is more than the 3% most shops and makers recommend.

215/50R17215/55R17Difference%
Overall diameter25.46"26.31"+0.85"+3.3%
Section width8.46"8.46"0.00"0.0%
Sidewall height4.23"4.66"+0.42"+10.0%
Circumference80.00"82.66"+2.66"+3.3%
Revolutions per mile792.0766.5−25.5−3.2%

Speedometer difference

If your vehicle came with 215/50R17 and you fit 215/55R17, 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, 215/50R17 or 215/55R17?
215/55R17 is taller by 0.85 inches (26.31" vs 25.46"). 215/50R17 is the same width.
Can I replace 215/50R17 with 215/55R17?
It is not recommended without checking carefully. The diameter difference is +3.3%, 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 215/55R17 change my speedometer?
When your speedometer reads 60 mph with 215/55R17 fitted (calibrated for 215/50R17), your real speed is 62.0 mph. Your odometer will under-count miles by about 3.3%.
Will 215/55R17 lift my vehicle?
Ride height changes by half the diameter difference: +0.42 inches of ground clearance at the axle.

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