Tire Size Box

245/65R15 vs 265/65R15

265/65R15 compared with 245/65R15

+3.7% diameter, +0.8" width

265/65R15 is 28.56" tall vs 27.54". More than the 3% rule of thumb, so check carefully before switching.

27.5"15" rim6.3"9.6" wide
245/65R15 (solid) compared with 265/65R15 (dashed outline), drawn to scale

With 265/65R15 tires, when your speedometer says 60 mph you are really going

62.2 mph

265/65R15 is +1.02 inches (+3.7%) in overall diameter. That is more than the 3% most shops and makers recommend.

245/65R15265/65R15Difference%
Overall diameter27.54"28.56"+1.02"+3.7%
Section width9.65"10.43"+0.79"+8.2%
Sidewall height6.27"6.78"+0.51"+8.2%
Circumference86.52"89.73"+3.22"+3.7%
Revolutions per mile732.3706.1−26.2−3.6%

Speedometer difference

If your vehicle came with 245/65R15 and you fit 265/65R15, here is your real speed for each speedometer reading:

Speedometer showsActual speedDifference
20 mph20.7 mph+0.7 mph
30 mph31.1 mph+1.1 mph
40 mph41.5 mph+1.5 mph
50 mph51.9 mph+1.9 mph
60 mph62.2 mph+2.2 mph
65 mph67.4 mph+2.4 mph
70 mph72.6 mph+2.6 mph
75 mph77.8 mph+2.8 mph
80 mph83.0 mph+3.0 mph

Each size on its own

Questions

Which is bigger, 245/65R15 or 265/65R15?
265/65R15 is taller by 1.02 inches (28.56" vs 27.54"). 265/65R15 is wider by 0.79 inches.
Can I replace 245/65R15 with 265/65R15?
It is not recommended without checking carefully. The diameter difference is +3.7%, 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 265/65R15 change my speedometer?
When your speedometer reads 60 mph with 265/65R15 fitted (calibrated for 245/65R15), your real speed is 62.2 mph. Your odometer will under-count miles by about 3.7%.
Will 265/65R15 lift my vehicle?
Ride height changes by half the diameter difference: +0.51 inches of ground clearance at the axle.

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