205/55R16 vs 205/60R15

Switching from 205/55R16 to 205/60R15 decreases the overall diameter by 4.9 mm (0.8%). That is within the usual ±3% guideline.

205/55R16205/60R15Difference (mm / revs)
Section width205 mm205 mm+0.0
Sidewall height112.8 mm123.0 mm+10.2
Rim diameter406.4 mm381.0 mm-25.4
Overall diameter631.9 mm627.0 mm-4.9
Circumference1,985.2 mm1,969.8 mm-15.4
Revolutions504 per km508 per km+4.0

Speedometer effect

With 205/60R15 fitted on a car calibrated for 205/55R16, the real speed when the speedometer shows:

Speedometer showsActual speed
50 km/h49.6 km/h
80 km/h79.4 km/h
100 km/h99.2 km/h
120 km/h119.1 km/h

Smaller tires make the speedometer read higher than the actual speed. Most speedometers also read slightly high from the factory.

Before you change size

205/55R16 dimensions · 205/60R15 dimensions · Open in calculator