255/60R15 vs 275/50R15

255/60R15 is 1.2" taller than 275/50R15 (4.5%)

Diameter difference−4.51%diameter 27.05" → 25.83"
255/60R15275/50R15
255/60R15275/50R15Difference
Overall diameter27.05"25.83"−1.22"
Section width10.04"10.83"+0.79"
Sidewall height6.02"5.41"−0.61"
Circumference85.0"81.1"−3.8"
Revolutions per mile746781+35
Wheel diameter15"15"±0"

Speedometer

ShowsActualDiff
30 mph28.6 mph−1.4
45 mph43.0 mph−2.0
60 mph57.3 mph−2.7
70 mph66.8 mph−3.2
80 mph76.4 mph−3.6

Gear ratio to match

CurrentEquivalent
3.423.27
3.553.39
3.733.56
4.103.91

275/50R15 is 1.22" shorter than 255/60R15, a −4.51% change in diameter. That is more than the 3% many tire shops use as a limit, so plan on recalibrating the speedometer and checking ABS and stability control.

Ground clearance changes by 0.61" (half the diameter change), and the tire needs 0.61" less room above it.

275/50R15 is 0.79" wider. On the same wheel offset about half of that, 0.39", moves toward the suspension and half toward the fender.

Both fit a 15" wheel; the sidewall is 0.61" shorter on 275/50R15.

Details: 255/60R15 in inches · 275/50R15 in inches · change sizes in the calculator

FAQ

What is the difference between 255/60R15 and 275/50R15?

275/50R15 is 1.22" shorter (−4.51%) and 0.79" wider than 255/60R15.

Will 275/50R15 change my speedometer?

Yes, by −4.51%. When the speedometer shows 60 mph you would be going 57.3 mph.

Can I replace 255/60R15 with 275/50R15?

It is a −4.5% diameter change, larger than the common 3% guideline, so check clearance and plan to recalibrate.