Tire Size Box

145/85R13 vs 165/80R13

165/80R13 compared with 145/85R13

+3.0% diameter, +0.8" width

165/80R13 is 23.39" tall vs 22.70". More than the 3% rule of thumb, so check carefully before switching.

22.7"13" rim4.9"5.7" wide
145/85R13 (solid) compared with 165/80R13 (dashed outline), drawn to scale

With 165/80R13 tires, when your speedometer says 60 mph you are really going

61.8 mph

165/80R13 is +0.69 inches (+3.0%) in overall diameter. That is more than the 3% most shops and makers recommend.

145/85R13165/80R13Difference%
Overall diameter22.70"23.39"+0.69"+3.0%
Section width5.71"6.50"+0.79"+13.8%
Sidewall height4.85"5.20"+0.34"+7.1%
Circumference71.33"73.49"+2.16"+3.0%
Revolutions per mile888.3862.1−26.2−2.9%

Speedometer difference

If your vehicle came with 145/85R13 and you fit 165/80R13, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.6 mph+0.6 mph
30 mph30.9 mph+0.9 mph
40 mph41.2 mph+1.2 mph
50 mph51.5 mph+1.5 mph
60 mph61.8 mph+1.8 mph
65 mph67.0 mph+2.0 mph
70 mph72.1 mph+2.1 mph
75 mph77.3 mph+2.3 mph
80 mph82.4 mph+2.4 mph

Each size on its own

Questions

Which is bigger, 145/85R13 or 165/80R13?
165/80R13 is taller by 0.69 inches (23.39" vs 22.70"). 165/80R13 is wider by 0.79 inches.
Can I replace 145/85R13 with 165/80R13?
It is not recommended without checking carefully. The diameter difference is +3.0%, 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 165/80R13 change my speedometer?
When your speedometer reads 60 mph with 165/80R13 fitted (calibrated for 145/85R13), your real speed is 61.8 mph. Your odometer will under-count miles by about 3.0%.
Will 165/80R13 lift my vehicle?
Ride height changes by half the diameter difference: +0.34 inches of ground clearance at the axle.

Other comparisons