Tire Size Box

265/80R16 vs 265/85R16

265/85R16 compared with 265/80R16

+3.2% diameter, 0.0" width

265/85R16 is 33.74" tall vs 32.69". More than the 3% rule of thumb, so check carefully before switching.

32.7"16" rim8.3"10.4" wide
265/80R16 (solid) compared with 265/85R16 (dashed outline), drawn to scale

With 265/85R16 tires, when your speedometer says 60 mph you are really going

61.9 mph

265/85R16 is +1.04 inches (+3.2%) in overall diameter. That is more than the 3% most shops and makers recommend.

265/80R16265/85R16Difference%
Overall diameter32.69"33.74"+1.04"+3.2%
Section width10.43"10.43"0.00"0.0%
Sidewall height8.35"8.87"+0.52"+6.2%
Circumference102.71"105.99"+3.28"+3.2%
Revolutions per mile616.9597.8−19.1−3.1%

Speedometer difference

If your vehicle came with 265/80R16 and you fit 265/85R16, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.6 mph+0.6 mph
30 mph31.0 mph+1.0 mph
40 mph41.3 mph+1.3 mph
50 mph51.6 mph+1.6 mph
60 mph61.9 mph+1.9 mph
65 mph67.1 mph+2.1 mph
70 mph72.2 mph+2.2 mph
75 mph77.4 mph+2.4 mph
80 mph82.6 mph+2.6 mph

Each size on its own

Questions

Which is bigger, 265/80R16 or 265/85R16?
265/85R16 is taller by 1.04 inches (33.74" vs 32.69"). 265/80R16 is the same width.
Can I replace 265/80R16 with 265/85R16?
It is not recommended without checking carefully. The diameter difference is +3.2%, 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 265/85R16 change my speedometer?
When your speedometer reads 60 mph with 265/85R16 fitted (calibrated for 265/80R16), your real speed is 61.9 mph. Your odometer will under-count miles by about 3.2%.
Will 265/85R16 lift my vehicle?
Ride height changes by half the diameter difference: +0.52 inches of ground clearance at the axle.

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