145/80R13 vs 165/70R14

165/70R14 is 0.96 in (24.4 mm) taller than 145/80R13, a +4.34% diameter difference. With the speedometer set for 145/80R13, an indicated 60 mph is 62.6 mph on 165/70R14.

Is this a safe swap?

Diameter difference +4.34%: outside the ±3% guideline

By overall diameter alone, 165/70R14 falls outside the ±3% range commonly used as a guideline when replacing 145/80R13; speedometer and ride-height changes are larger. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

Side profile and tread width, drawn to the same scale.

145/80R13 vs 165/70R14 differences
Measurement	145/80R13	165/70R14	Difference	% diff
Overall diameter	22.13 in (562.2 mm)	23.09 in (586.6 mm)	+0.96 in (+24.4 mm)	+4.34%
Sidewall height	4.57 in (116.0 mm)	4.55 in (115.5 mm)	−0.02 in (−0.5 mm)	−0.43%
Section width	5.71 in (145.0 mm)	6.50 in (165.0 mm)	+0.79 in (+20.0 mm)	+13.79%
Circumference	69.54 in (1,766.2 mm)	72.55 in (1,842.9 mm)	+3.02 in (+76.7 mm)	+4.34%
Revolutions per mile	911	873	−38	−4.16%

True speed with the speedometer calibrated for 145/80R13
Indicated	Actual on 145/80R13	Actual on 165/70R14	Difference
30 mph	30.0 mph	31.3 mph	+1.3 mph
60 mph	60.0 mph	62.6 mph	+2.6 mph
75 mph	75.0 mph	78.3 mph	+3.3 mph

Ride-height change: 165/70R14 raises the vehicle by 0.48 in (12.2 mm) at the axle (half the +24.4 mm diameter difference).

165/70R14 is 0.96 in taller than 145/80R13 and 20 mm wider, a 4.34% difference in overall diameter.

With the speedometer calibrated for 145/80R13, an indicated 60 mph is actually 62.6 mph on 165/70R14, and revolutions per mile change from 911 to 873.

165/70R14 mounts on a 14-inch wheel, a plus-1 fitment from the 13-inch wheel of 145/80R13.

Size pages

Other comparisons with 145/80R13

Other comparisons with 165/70R14

Source: Calculated from standard tire geometry formulas. Verified 2026-09-27. How these numbers are calculated.