Tire Size Box

245/50R15 vs 265/50R15

265/50R15 compared with 245/50R15

+3.2% diameter, +0.8" width

265/50R15 is 25.43" tall vs 24.65". More than the 3% rule of thumb, so check carefully before switching.

24.6"15" rim4.8"9.6" wide
245/50R15 (solid) compared with 265/50R15 (dashed outline), drawn to scale

With 265/50R15 tires, when your speedometer says 60 mph you are really going

61.9 mph

265/50R15 is +0.79 inches (+3.2%) in overall diameter. That is more than the 3% most shops and makers recommend.

245/50R15265/50R15Difference%
Overall diameter24.65"25.43"+0.79"+3.2%
Section width9.65"10.43"+0.79"+8.2%
Sidewall height4.82"5.22"+0.39"+8.2%
Circumference77.43"79.90"+2.47"+3.2%
Revolutions per mile818.3793.0−25.3−3.1%

Speedometer difference

If your vehicle came with 245/50R15 and you fit 265/50R15, 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, 245/50R15 or 265/50R15?
265/50R15 is taller by 0.79 inches (25.43" vs 24.65"). 265/50R15 is wider by 0.79 inches.
Can I replace 245/50R15 with 265/50R15?
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 265/50R15 change my speedometer?
When your speedometer reads 60 mph with 265/50R15 fitted (calibrated for 245/50R15), your real speed is 61.9 mph. Your odometer will under-count miles by about 3.2%.
Will 265/50R15 lift my vehicle?
Ride height changes by half the diameter difference: +0.39 inches of ground clearance at the axle.

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