Tire Size Box

215/70R15 vs 215/80R15

215/80R15 compared with 215/70R15

+6.3% diameter, 0.0" width

215/80R15 is 28.54" 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 215/80R15 (dashed outline), drawn to scale

With 215/80R15 tires, when your speedometer says 60 mph you are really going

63.8 mph

215/80R15 is +1.69 inches (+6.3%) in overall diameter. That is more than the 3% most shops and makers recommend.

215/70R15215/80R15Difference%
Overall diameter26.85"28.54"+1.69"+6.3%
Section width8.46"8.46"0.00"0.0%
Sidewall height5.93"6.77"+0.85"+14.3%
Circumference84.35"89.67"+5.32"+6.3%
Revolutions per mile751.1706.6−44.5−5.9%

Speedometer difference

If your vehicle came with 215/70R15 and you fit 215/80R15, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph21.3 mph+1.3 mph
30 mph31.9 mph+1.9 mph
40 mph42.5 mph+2.5 mph
50 mph53.2 mph+3.2 mph
60 mph63.8 mph+3.8 mph
65 mph69.1 mph+4.1 mph
70 mph74.4 mph+4.4 mph
75 mph79.7 mph+4.7 mph
80 mph85.0 mph+5.0 mph

Each size on its own

Questions

Which is bigger, 215/70R15 or 215/80R15?
215/80R15 is taller by 1.69 inches (28.54" vs 26.85"). 215/70R15 is the same width.
Can I replace 215/70R15 with 215/80R15?
It is not recommended without checking carefully. The diameter difference is +6.3%, 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 215/80R15 change my speedometer?
When your speedometer reads 60 mph with 215/80R15 fitted (calibrated for 215/70R15), your real speed is 63.8 mph. Your odometer will under-count miles by about 6.3%.
Will 215/80R15 lift my vehicle?
Ride height changes by half the diameter difference: +0.85 inches of ground clearance at the axle.

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