Tire Size Box

215/65R15 vs 235/65R15

235/65R15 compared with 215/65R15

+3.9% diameter, +0.8" width

235/65R15 is 27.03" tall vs 26.00". More than the 3% rule of thumb, so check carefully before switching.

26.0"15" rim5.5"8.5" wide
215/65R15 (solid) compared with 235/65R15 (dashed outline), drawn to scale

With 235/65R15 tires, when your speedometer says 60 mph you are really going

62.4 mph

235/65R15 is +1.02 inches (+3.9%) in overall diameter. That is more than the 3% most shops and makers recommend.

215/65R15235/65R15Difference%
Overall diameter26.00"27.03"+1.02"+3.9%
Section width8.46"9.25"+0.79"+9.3%
Sidewall height5.50"6.01"+0.51"+9.3%
Circumference81.69"84.91"+3.22"+3.9%
Revolutions per mile775.6746.2−29.4−3.8%

Speedometer difference

If your vehicle came with 215/65R15 and you fit 235/65R15, 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 mph83.1 mph+3.1 mph

Each size on its own

Questions

Which is bigger, 215/65R15 or 235/65R15?
235/65R15 is taller by 1.02 inches (27.03" vs 26.00"). 235/65R15 is wider by 0.79 inches.
Can I replace 215/65R15 with 235/65R15?
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 235/65R15 change my speedometer?
When your speedometer reads 60 mph with 235/65R15 fitted (calibrated for 215/65R15), your real speed is 62.4 mph. Your odometer will under-count miles by about 3.9%.
Will 235/65R15 lift my vehicle?
Ride height changes by half the diameter difference: +0.51 inches of ground clearance at the axle.

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