215/70R15 vs 225/60R16

Switching from 215/70R15 to 225/60R16 decreases the overall diameter by 5.6 mm (0.8%). That is within the usual ±3% guideline.

215/70R15225/60R16Difference (mm / revs)
Section width215 mm225 mm+10.0
Sidewall height150.5 mm135.0 mm-15.5
Rim diameter381.0 mm406.4 mm+25.4
Overall diameter682.0 mm676.4 mm-5.6
Circumference2,142.6 mm2,125.0 mm-17.6
Revolutions467 per km471 per km+4.0

Speedometer effect

With 225/60R16 fitted on a car calibrated for 215/70R15, the real speed when the speedometer shows:

Speedometer showsActual speed
50 km/h49.6 km/h
80 km/h79.3 km/h
100 km/h99.2 km/h
120 km/h119.0 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

215/70R15 dimensions · 225/60R16 dimensions · Open in calculator