Tire Size Box

215/70R15 vs 235/70R15

235/70R15 compared with 215/70R15

+4.1% diameter, +0.8" width

235/70R15 is 27.95" tall vs 26.85". More than the 3% rule of thumb, so check carefully before switching.

26.9"15" rim5.9"8.5" wide
215/70R15 (solid) compared with 235/70R15 (dashed outline), drawn to scale

With 235/70R15 tires, when your speedometer says 60 mph you are really going

62.5 mph

235/70R15 is +1.10 inches (+4.1%) in overall diameter. That is more than the 3% most shops and makers recommend.

215/70R15235/70R15Difference%
Overall diameter26.85"27.95"+1.10"+4.1%
Section width8.46"9.25"+0.79"+9.3%
Sidewall height5.93"6.48"+0.55"+9.3%
Circumference84.35"87.82"+3.46"+4.1%
Revolutions per mile751.1721.5−29.6−3.9%

Speedometer difference

If your vehicle came with 215/70R15 and you fit 235/70R15, 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 mph52.1 mph+2.1 mph
60 mph62.5 mph+2.5 mph
65 mph67.7 mph+2.7 mph
70 mph72.9 mph+2.9 mph
75 mph78.1 mph+3.1 mph
80 mph83.3 mph+3.3 mph

Each size on its own

Questions

Which is bigger, 215/70R15 or 235/70R15?
235/70R15 is taller by 1.10 inches (27.95" vs 26.85"). 235/70R15 is wider by 0.79 inches.
Can I replace 215/70R15 with 235/70R15?
It is not recommended without checking carefully. The diameter difference is +4.1%, 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 235/70R15 change my speedometer?
When your speedometer reads 60 mph with 235/70R15 fitted (calibrated for 215/70R15), your real speed is 62.5 mph. Your odometer will under-count miles by about 4.1%.
Will 235/70R15 lift my vehicle?
Ride height changes by half the diameter difference: +0.55 inches of ground clearance at the axle.

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