215/70R16 vs 235/65R16

Switching from 215/70R16 to 235/65R16 increases the overall diameter by 4.5 mm (0.6%). That is within the usual ±3% guideline.

215/70R16235/65R16Difference (mm / revs)
Section width215 mm235 mm+20.0
Sidewall height150.5 mm152.8 mm+2.3
Rim diameter406.4 mm406.4 mm+0.0
Overall diameter707.4 mm711.9 mm+4.5
Circumference2,222.4 mm2,236.5 mm+14.1
Revolutions450 per km447 per km-3.0

Speedometer effect

With 235/65R16 fitted on a car calibrated for 215/70R16, the real speed when the speedometer shows:

Speedometer showsActual speed
50 km/h50.3 km/h
80 km/h80.5 km/h
100 km/h100.6 km/h
120 km/h120.8 km/h

Larger tires make the car go faster than the speedometer shows. Most speedometers also read slightly high from the factory.

Before you change size

215/70R16 dimensions · 235/65R16 dimensions · Open in calculator