Tire Size Box

275/75R16 vs 275/80R16

275/80R16 compared with 275/75R16

+3.4% diameter, 0.0" width

275/80R16 is 33.32" tall vs 32.24". More than the 3% rule of thumb, so check carefully before switching.

32.2"16" rim8.1"10.8" wide
275/75R16 (solid) compared with 275/80R16 (dashed outline), drawn to scale

With 275/80R16 tires, when your speedometer says 60 mph you are really going

62.0 mph

275/80R16 is +1.08 inches (+3.4%) in overall diameter. That is more than the 3% most shops and makers recommend.

275/75R16275/80R16Difference%
Overall diameter32.24"33.32"+1.08"+3.4%
Section width10.83"10.83"0.00"0.0%
Sidewall height8.12"8.66"+0.54"+6.7%
Circumference101.29"104.69"+3.40"+3.4%
Revolutions per mile625.6605.2−20.3−3.2%

Speedometer difference

If your vehicle came with 275/75R16 and you fit 275/80R16, 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 mph72.4 mph+2.4 mph
75 mph77.5 mph+2.5 mph
80 mph82.7 mph+2.7 mph

Each size on its own

Questions

Which is bigger, 275/75R16 or 275/80R16?
275/80R16 is taller by 1.08 inches (33.32" vs 32.24"). 275/75R16 is the same width.
Can I replace 275/75R16 with 275/80R16?
It is not recommended without checking carefully. The diameter difference is +3.4%, 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 275/80R16 change my speedometer?
When your speedometer reads 60 mph with 275/80R16 fitted (calibrated for 275/75R16), your real speed is 62.0 mph. Your odometer will under-count miles by about 3.4%.
Will 275/80R16 lift my vehicle?
Ride height changes by half the diameter difference: +0.54 inches of ground clearance at the axle.

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