TireSizesFinder

165/80R13 vs 205/50R15

205/50R15 is 0.32 in (8.2 mm) shorter than 165/80R13, a −1.38% diameter difference. With the speedometer set for 165/80R13, an indicated 60 mph is 59.2 mph on 205/50R15.

Is this a safe swap?

Diameter difference −1.38%: within the ±3% guideline

By overall diameter alone, 205/50R15 falls inside the ±3% range commonly used as a guideline when replacing 165/80R13. This check uses diameter only. It does not assess load index, speed rating, wheel width or clearance.

To-scale drawing: 165/80R13 (23.39 in) vs 205/50R15 (23.07 in)165/80R1323.39 in × 6.50 in205/50R1523.07 in × 8.07 in
Side profile and tread width, drawn to the same scale.
165/80R13 vs 205/50R15 differences
Measurement165/80R13205/50R15Difference% diff
Overall diameter23.39 in (594.2 mm)23.07 in (586.0 mm)−0.32 in (−8.2 mm)−1.38%
Sidewall height5.20 in (132.0 mm)4.04 in (102.5 mm)−1.16 in (−29.5 mm)−22.35%
Section width6.50 in (165.0 mm)8.07 in (205.0 mm)+1.57 in (+40.0 mm)+24.24%
Circumference73.49 in (1,866.7 mm)72.48 in (1,841.0 mm)−1.01 in (−25.8 mm)−1.38%
Revolutions per mile862874+12+1.40%
True speed with the speedometer calibrated for 165/80R13
IndicatedActual on 165/80R13Actual on 205/50R15Difference
30 mph30.0 mph29.6 mph−0.4 mph
60 mph60.0 mph59.2 mph−0.8 mph
75 mph75.0 mph74.0 mph−1.0 mph

Ride-height change: 205/50R15 lowers the vehicle by 0.16 in (4.1 mm) at the axle (half the −8.2 mm diameter difference).

205/50R15 is 0.32 in shorter than 165/80R13 and 40 mm wider, a 1.38% difference in overall diameter.

With the speedometer calibrated for 165/80R13, an indicated 60 mph is actually 59.2 mph on 205/50R15, and revolutions per mile change from 862 to 874.

205/50R15 mounts on a 15-inch wheel, a plus-2 fitment from the 13-inch wheel of 165/80R13.

Size pages

Other comparisons with 165/80R13

Other comparisons with 205/50R15

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