Skip to content
GizmoDriver

225/45R17 vs 255/35R18 tire size

255/35R18 vs 225/45R17, diameter

+0.2% taller

Speedometer
59.9 mph
At a true 60 mph
Diameter
25.03 in
Was 24.97 in
Revs per mile
806
Was 808
3% guideline
Within

Car built for 225/45R17, now on 255/35R18.

225/45R17 and 255/35R18

225/45R17 vs 255/35R18 tire size
Measure225/45R17255/35R18Difference
Width, mm225255+30
Sidewall, % of width4535-10
Rim, in1718+1
Section height, in3.993.51-0.47
Diameter, in24.9725.03+0.06 (+0.2%)
Circumference, in78.578.6+0.2
Revs per mile808806-2 (-0.2%)

Fitting 255/35R18 instead of 225/45R17

Within the usual 3% diameter guideline.

  • Needs 18 in wheels.
  • 30 mm wider. Check rubbing at full lock.

Cars with 225/45R17

Cars with 255/35R18

What this cannot tell you

Diameter within 3% is a common shop guideline, not a maker spec.

Load index, offset and clearance are not in this data.

How values are checked