TireSizesFinder

205/65R15 vs 245/45R17

245/45R17 is 0.19 in (4.8 mm) taller than 205/65R15, a +0.74% diameter difference. With the speedometer set for 205/65R15, an indicated 60 mph is 60.4 mph on 245/45R17.

Is this a safe swap?

Diameter difference +0.74%: under 1%

By overall diameter alone, 245/45R17 is a near match for 205/65R15; 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: 205/65R15 (25.49 in) vs 245/45R17 (25.68 in)205/65R1525.49 in × 8.07 in245/45R1725.68 in × 9.65 in
Side profile and tread width, drawn to the same scale.
205/65R15 vs 245/45R17 differences
Measurement205/65R15245/45R17Difference% diff
Overall diameter25.49 in (647.5 mm)25.68 in (652.3 mm)+0.19 in (+4.8 mm)+0.74%
Sidewall height5.25 in (133.3 mm)4.34 in (110.3 mm)−0.91 in (−23.0 mm)−17.26%
Section width8.07 in (205.0 mm)9.65 in (245.0 mm)+1.57 in (+40.0 mm)+19.51%
Circumference80.09 in (2,034.2 mm)80.68 in (2,049.3 mm)+0.59 in (+15.1 mm)+0.74%
Revolutions per mile791785−6−0.74%
True speed with the speedometer calibrated for 205/65R15
IndicatedActual on 205/65R15Actual on 245/45R17Difference
30 mph30.0 mph30.2 mph+0.2 mph
60 mph60.0 mph60.4 mph+0.4 mph
75 mph75.0 mph75.6 mph+0.6 mph

Ride-height change: 245/45R17 raises the vehicle by 0.09 in (2.4 mm) at the axle (half the +4.8 mm diameter difference).

245/45R17 is 0.19 in taller than 205/65R15 and 40 mm wider, a 0.74% difference in overall diameter.

With the speedometer calibrated for 205/65R15, an indicated 60 mph is actually 60.4 mph on 245/45R17, and revolutions per mile change from 791 to 785.

245/45R17 mounts on a 17-inch wheel, a plus-2 fitment from the 15-inch wheel of 205/65R15.

Size pages

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