205/65R15 vs 215/55R16

Switching from 205/65R15 to 215/55R16 decreases the overall diameter by 4.6 mm (0.7%). That is within the usual ±3% guideline.

205/65R15215/55R16Difference (mm / revs)
Section width205 mm215 mm+10.0
Sidewall height133.2 mm118.2 mm-15.0
Rim diameter381.0 mm406.4 mm+25.4
Overall diameter647.5 mm642.9 mm-4.6
Circumference2,034.2 mm2,019.7 mm-14.5
Revolutions492 per km495 per km+3.0

Speedometer effect

With 215/55R16 fitted on a car calibrated for 205/65R15, the real speed when the speedometer shows:

Speedometer showsActual speed
50 km/h49.6 km/h
80 km/h79.4 km/h
100 km/h99.3 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

205/65R15 dimensions · 215/55R16 dimensions · Open in calculator