225/70R15 vs 255/60R15

225/70R15 is 0.4" taller than 255/60R15 (1.3%)

Diameter difference−1.29%diameter 27.40" → 27.05"
225/70R15255/60R15
225/70R15255/60R15Difference
Overall diameter27.40"27.05"−0.35"
Section width8.86"10.04"+1.18"
Sidewall height6.20"6.02"−0.18"
Circumference86.1"85.0"−1.1"
Revolutions per mile736746+10
Wheel diameter15"15"±0"

Speedometer

ShowsActualDiff
30 mph29.6 mph−0.4
45 mph44.4 mph−0.6
60 mph59.2 mph−0.8
70 mph69.1 mph−0.9
80 mph79.0 mph−1.0

Gear ratio to match

CurrentEquivalent
3.423.38
3.553.50
3.733.68
4.104.05

255/60R15 is 0.35" shorter than 225/70R15, a −1.29% change in diameter, inside the 3% range most shops treat as a safe swap.

Ground clearance changes by 0.18" (half the diameter change), and the tire needs 0.18" less room above it.

255/60R15 is 1.18" wider. On the same wheel offset about half of that, 0.59", moves toward the suspension and half toward the fender.

Both fit a 15" wheel; the sidewall is 0.18" shorter on 255/60R15.

Details: 225/70R15 in inches · 255/60R15 in inches · change sizes in the calculator

FAQ

What is the difference between 225/70R15 and 255/60R15?

255/60R15 is 0.35" shorter (−1.29%) and 1.18" wider than 225/70R15.

Will 255/60R15 change my speedometer?

Yes, by −1.29%. When the speedometer shows 60 mph you would be going 59.2 mph.

Can I replace 225/70R15 with 255/60R15?

Often yes: the diameter change of −1.3% is within the common 3% guideline. Check the load index, speed rating and clearance.