215/70R16 vs 225/60R17

Switching from 215/70R16 to 225/60R17 decreases the overall diameter by 5.6 mm (0.8%). That is within the usual ±3% guideline.

215/70R16225/60R17Difference (mm / revs)
Section width215 mm225 mm+10.0
Sidewall height150.5 mm135.0 mm-15.5
Rim diameter406.4 mm431.8 mm+25.4
Overall diameter707.4 mm701.8 mm-5.6
Circumference2,222.4 mm2,204.8 mm-17.6
Revolutions450 per km454 per km+4.0

Speedometer effect

With 225/60R17 fitted on a car calibrated for 215/70R16, 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

215/70R16 dimensions · 225/60R17 dimensions · Open in calculator