265/60R20 vs 275/55R20

265/60R20 is 0.6" taller than 275/55R20 (1.9%)

Diameter difference−1.88%diameter 32.52" → 31.91"
265/60R20275/55R20
265/60R20275/55R20Difference
Overall diameter32.52"31.91"−0.61"
Section width10.43"10.83"+0.39"
Sidewall height6.26"5.95"−0.31"
Circumference102.2"100.2"−1.9"
Revolutions per mile620632+12
Wheel diameter20"20"±0"

Speedometer

ShowsActualDiff
30 mph29.4 mph−0.6
45 mph44.2 mph−0.8
60 mph58.9 mph−1.1
70 mph68.7 mph−1.3
80 mph78.5 mph−1.5

Gear ratio to match

CurrentEquivalent
3.423.36
3.553.48
3.733.66
4.104.02

275/55R20 is 0.61" shorter than 265/60R20, a −1.88% change in diameter, inside the 3% range most shops treat as a safe swap.

Ground clearance changes by 0.31" (half the diameter change), and the tire needs 0.31" less room above it.

275/55R20 is 0.39" wider. On the same wheel offset about half of that, 0.20", moves toward the suspension and half toward the fender.

Both fit a 20" wheel; the sidewall is 0.31" shorter on 275/55R20.

Details: 265/60R20 in inches · 275/55R20 in inches · change sizes in the calculator

FAQ

What is the difference between 265/60R20 and 275/55R20?

275/55R20 is 0.61" shorter (−1.88%) and 0.39" wider than 265/60R20.

Will 275/55R20 change my speedometer?

Yes, by −1.88%. When the speedometer shows 60 mph you would be going 58.9 mph.

Can I replace 265/60R20 with 275/55R20?

Often yes: the diameter change of −1.9% is within the common 3% guideline. Check the load index, speed rating and clearance.