Tire Size Box

205/70R15 vs 225/70R15

225/70R15 compared with 205/70R15

+4.2% diameter, +0.8" width

225/70R15 is 27.40" tall vs 26.30". More than the 3% rule of thumb, so check carefully before switching.

26.3"15" rim5.6"8.1" wide
205/70R15 (solid) compared with 225/70R15 (dashed outline), drawn to scale

With 225/70R15 tires, when your speedometer says 60 mph you are really going

62.5 mph

225/70R15 is +1.10 inches (+4.2%) in overall diameter. That is more than the 3% most shops and makers recommend.

205/70R15225/70R15Difference%
Overall diameter26.30"27.40"+1.10"+4.2%
Section width8.07"8.86"+0.79"+9.8%
Sidewall height5.65"6.20"+0.55"+9.8%
Circumference82.62"86.08"+3.46"+4.2%
Revolutions per mile766.9736.0−30.9−4.0%

Speedometer difference

If your vehicle came with 205/70R15 and you fit 225/70R15, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.8 mph+0.8 mph
30 mph31.3 mph+1.3 mph
40 mph41.7 mph+1.7 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 mph83.4 mph+3.4 mph

Each size on its own

Questions

Which is bigger, 205/70R15 or 225/70R15?
225/70R15 is taller by 1.10 inches (27.40" vs 26.30"). 225/70R15 is wider by 0.79 inches.
Can I replace 205/70R15 with 225/70R15?
It is not recommended without checking carefully. The diameter difference is +4.2%, 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 225/70R15 change my speedometer?
When your speedometer reads 60 mph with 225/70R15 fitted (calibrated for 205/70R15), your real speed is 62.5 mph. Your odometer will under-count miles by about 4.2%.
Will 225/70R15 lift my vehicle?
Ride height changes by half the diameter difference: +0.55 inches of ground clearance at the axle.

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