205/65R15 vs 235/35R19

Switching from 205/65R15 to 235/35R19 decreases the overall diameter by 0.4 mm (0.1%). That is within the usual ±3% guideline.

205/65R15235/35R19Difference (mm / revs)
Section width205 mm235 mm+30.0
Sidewall height133.2 mm82.2 mm-51.0
Rim diameter381.0 mm482.6 mm+101.6
Overall diameter647.5 mm647.1 mm-0.4
Circumference2,034.2 mm2,032.9 mm-1.3
Revolutions492 per km492 per km+0.0

Speedometer effect

With 235/35R19 fitted on a car calibrated for 205/65R15, the real speed when the speedometer shows:

Speedometer showsActual speed
50 km/h50.0 km/h
80 km/h80.0 km/h
100 km/h99.9 km/h
120 km/h119.9 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 · 235/35R19 dimensions · Open in calculator