275/60R18 vs 265/65R18

265/65R18 is 0.6" taller than 275/60R18 (1.8%)

Diameter difference+1.84%diameter 30.99" → 31.56"
275/60R18265/65R18
275/60R18265/65R18Difference
Overall diameter30.99"31.56"+0.57"
Section width10.83"10.43"−0.39"
Sidewall height6.50"6.78"+0.29"
Circumference97.4"99.2"+1.8"
Revolutions per mile651639−12
Wheel diameter18"18"±0"

Speedometer

ShowsActualDiff
30 mph30.6 mph+0.6
45 mph45.8 mph+0.8
60 mph61.1 mph+1.1
70 mph71.3 mph+1.3
80 mph81.5 mph+1.5

Gear ratio to match

CurrentEquivalent
3.423.48
3.553.62
3.733.80
4.104.18

265/65R18 is 0.57" taller than 275/60R18, a +1.84% change in diameter, inside the 3% range most shops treat as a safe swap.

Ground clearance changes by 0.29" (half the diameter change), and the tire needs 0.29" more room above it.

275/60R18 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 18" wheel; the sidewall is 0.29" taller on 265/65R18.

Details: 275/60R18 in inches · 265/65R18 in inches · change sizes in the calculator

FAQ

What is the difference between 275/60R18 and 265/65R18?

265/65R18 is 0.57" taller (+1.84%) and 0.39" narrower than 275/60R18.

Will 265/65R18 change my speedometer?

Yes, by +1.84%. When the speedometer shows 60 mph you would be going 61.1 mph.

Can I replace 275/60R18 with 265/65R18?

Often yes: the diameter change of +1.8% is within the common 3% guideline. Check the load index, speed rating and clearance.