245/60R16 vs 265/45R18

265/45R18 is 0.19 in (4.7 mm) shorter than 245/60R16, a −0.67% diameter difference. With the speedometer set for 245/60R16, an indicated 60 mph is 59.6 mph on 265/45R18.

Is this a safe swap?

Diameter difference −0.67%: under 1%

By overall diameter alone, 265/45R18 is a near match for 245/60R16; 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: 245/60R16 (27.57 in) vs 265/45R18 (27.39 in)245/60R1627.57 in × 9.65 in265/45R1827.39 in × 10.43 in
Side profile and tread width, drawn to the same scale.
245/60R16 vs 265/45R18 differences
Measurement245/60R16265/45R18Difference% diff
Overall diameter27.57 in (700.4 mm)27.39 in (695.7 mm)−0.19 in (−4.7 mm)−0.67%
Sidewall height5.79 in (147.0 mm)4.69 in (119.3 mm)−1.09 in (−27.7 mm)−18.88%
Section width9.65 in (245.0 mm)10.43 in (265.0 mm)+0.79 in (+20.0 mm)+8.16%
Circumference86.63 in (2,200.4 mm)86.05 in (2,185.6 mm)−0.58 in (−14.8 mm)−0.67%
Revolutions per mile731736+5+0.68%
True speed with the speedometer calibrated for 245/60R16
IndicatedActual on 245/60R16Actual on 265/45R18Difference
30 mph30.0 mph29.8 mph−0.2 mph
60 mph60.0 mph59.6 mph−0.4 mph
75 mph75.0 mph74.5 mph−0.5 mph

Ride-height change: 265/45R18 lowers the vehicle by 0.09 in (2.3 mm) at the axle (half the −4.7 mm diameter difference).

265/45R18 is 0.19 in shorter than 245/60R16 and 20 mm wider, a 0.67% difference in overall diameter.

With the speedometer calibrated for 245/60R16, an indicated 60 mph is actually 59.6 mph on 265/45R18, and revolutions per mile change from 731 to 736.

265/45R18 mounts on a 18-inch wheel, a plus-2 fitment from the 16-inch wheel of 245/60R16.

Size pages

Other comparisons with 245/60R16

Other comparisons with 265/45R18

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