285/70R17 vs 33x12.50R17

33x12.50R17 is 0.3" taller than 285/70R17 (0.9%)

Diameter difference+0.89%diameter 32.71" → 33.00"
285/70R1733x12.50R17
285/70R1733x12.50R17Difference
Overall diameter32.71"33.00"+0.29"
Section width11.22"12.50"+1.28"
Sidewall height7.85"8.00"+0.15"
Circumference102.8"103.7"+0.9"
Revolutions per mile617611−5
Wheel diameter17"17"±0"

Speedometer

ShowsActualDiff
30 mph30.3 mph+0.3
45 mph45.4 mph+0.4
60 mph60.5 mph+0.5
70 mph70.6 mph+0.6
80 mph80.7 mph+0.7

Gear ratio to match

CurrentEquivalent
3.423.45
3.553.58
3.733.76
4.104.14

33x12.50R17 is 0.29" taller than 285/70R17, a +0.89% change in diameter, inside the 3% range most shops treat as a safe swap.

Ground clearance changes by 0.15" (half the diameter change), and the tire needs 0.15" more room above it.

33x12.50R17 is 1.28" wider. On the same wheel offset about half of that, 0.64", moves toward the suspension and half toward the fender.

Both fit a 17" wheel; the sidewall is 0.15" taller on 33x12.50R17.

Details: 285/70R17 in inches · 33x12.50R17 in inches · change sizes in the calculator

FAQ

What is the difference between 285/70R17 and 33x12.50R17?

33x12.50R17 is 0.29" taller (+0.89%) and 1.28" wider than 285/70R17.

Will 33x12.50R17 change my speedometer?

Yes, by +0.89%. When the speedometer shows 60 mph you would be going 60.5 mph.

Can I replace 285/70R17 with 33x12.50R17?

Often yes: the diameter change of +0.9% is within the common 3% guideline. Check the load index, speed rating and clearance.