235/60R15 vs 255/60R15

255/60R15 is 0.9" taller than 235/60R15 (3.6%)

Diameter difference+3.62%diameter 26.10" → 27.05"
235/60R15255/60R15
235/60R15255/60R15Difference
Overall diameter26.10"27.05"+0.94"
Section width9.25"10.04"+0.79"
Sidewall height5.55"6.02"+0.47"
Circumference82.0"85.0"+3.0"
Revolutions per mile773746−27
Wheel diameter15"15"±0"

Speedometer

ShowsActualDiff
30 mph31.1 mph+1.1
45 mph46.6 mph+1.6
60 mph62.2 mph+2.2
70 mph72.5 mph+2.5
80 mph82.9 mph+2.9

Gear ratio to match

CurrentEquivalent
3.423.54
3.553.68
3.733.87
4.104.25

255/60R15 is 0.94" taller than 235/60R15, a +3.62% 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 0.47" (half the diameter change), and the tire needs 0.47" more room above it.

255/60R15 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 0.47" taller on 255/60R15.

Details: 235/60R15 in inches · 255/60R15 in inches · change sizes in the calculator

FAQ

What is the difference between 235/60R15 and 255/60R15?

255/60R15 is 0.94" taller (+3.62%) and 0.79" wider than 235/60R15.

Will 255/60R15 change my speedometer?

Yes, by +3.62%. When the speedometer shows 60 mph you would be going 62.2 mph.

Can I replace 235/60R15 with 255/60R15?

It is a +3.6% diameter change, larger than the common 3% guideline, so check clearance and plan to recalibrate.