TireSizesFinder

185/60R13 vs 145/80R13

145/80R13 is 0.39 in (10.0 mm) taller than 185/60R13, a +1.81% diameter difference. With the speedometer set for 185/60R13, an indicated 60 mph is 61.1 mph on 145/80R13.

Is this a safe swap?

Diameter difference +1.81%: within the ±3% guideline

By overall diameter alone, 145/80R13 falls inside the ±3% range commonly used as a guideline when replacing 185/60R13. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 185/60R13 (21.74 in) vs 145/80R13 (22.13 in)185/60R1321.74 in × 7.28 in145/80R1322.13 in × 5.71 in
Side profile and tread width, drawn to the same scale.
185/60R13 vs 145/80R13 differences
Measurement185/60R13145/80R13Difference% diff
Overall diameter21.74 in (552.2 mm)22.13 in (562.2 mm)+0.39 in (+10.0 mm)+1.81%
Sidewall height4.37 in (111.0 mm)4.57 in (116.0 mm)+0.20 in (+5.0 mm)+4.50%
Section width7.28 in (185.0 mm)5.71 in (145.0 mm)−1.57 in (−40.0 mm)−21.62%
Circumference68.30 in (1,734.8 mm)69.54 in (1,766.2 mm)+1.24 in (+31.4 mm)+1.81%
Revolutions per mile928911−17−1.78%
True speed with the speedometer calibrated for 185/60R13
IndicatedActual on 185/60R13Actual on 145/80R13Difference
30 mph30.0 mph30.5 mph+0.5 mph
60 mph60.0 mph61.1 mph+1.1 mph
75 mph75.0 mph76.4 mph+1.4 mph

Ride-height change: 145/80R13 raises the vehicle by 0.20 in (5.0 mm) at the axle (half the +10.0 mm diameter difference).

145/80R13 is 0.39 in taller than 185/60R13 and 40 mm narrower, a 1.81% difference in overall diameter.

With the speedometer calibrated for 185/60R13, an indicated 60 mph is actually 61.1 mph on 145/80R13, and revolutions per mile change from 928 to 911.

Both sizes mount on 13-inch wheels.

Size pages

Other comparisons with 185/60R13

Other comparisons with 145/80R13

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