TireSizesFinder

265/60R17 vs 245/60R18

245/60R18 is 0.06 in (1.4 mm) taller than 265/60R17, a +0.19% diameter difference. With the speedometer set for 265/60R17, an indicated 60 mph is 60.1 mph on 245/60R18.

Is this a safe swap?

Diameter difference +0.19%: under 1%

By overall diameter alone, 245/60R18 is a near match for 265/60R17; the speedometer changes by less than 1%. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 265/60R17 (29.52 in) vs 245/60R18 (29.57 in)265/60R1729.52 in × 10.43 in245/60R1829.57 in × 9.65 in
Side profile and tread width, drawn to the same scale.
265/60R17 vs 245/60R18 differences
Measurement265/60R17245/60R18Difference% diff
Overall diameter29.52 in (749.8 mm)29.57 in (751.2 mm)+0.06 in (+1.4 mm)+0.19%
Sidewall height6.26 in (159.0 mm)5.79 in (147.0 mm)−0.47 in (−12.0 mm)−7.55%
Section width10.43 in (265.0 mm)9.65 in (245.0 mm)−0.79 in (−20.0 mm)−7.55%
Circumference92.74 in (2,355.6 mm)92.91 in (2,360.0 mm)+0.17 in (+4.4 mm)+0.19%
Revolutions per mile683682−1−0.19%
True speed with the speedometer calibrated for 265/60R17
IndicatedActual on 265/60R17Actual on 245/60R18Difference
30 mph30.0 mph30.1 mph+0.1 mph
60 mph60.0 mph60.1 mph+0.1 mph
75 mph75.0 mph75.1 mph+0.1 mph

Ride-height change: 245/60R18 raises the vehicle by 0.03 in (0.7 mm) at the axle (half the +1.4 mm diameter difference).

245/60R18 is 0.06 in taller than 265/60R17 and 20 mm narrower, a 0.19% difference in overall diameter.

With the speedometer calibrated for 265/60R17, an indicated 60 mph is actually 60.1 mph on 245/60R18, and revolutions per mile change from 683 to 682.

245/60R18 mounts on a 18-inch wheel, a plus-1 fitment from the 17-inch wheel of 265/60R17.

Size pages

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Source: Calculated from standard tire geometry formulas. Verified . How these numbers are calculated.