245/75R16 vs 265/70R16

Switching from 245/75R16 to 265/70R16 increases the overall diameter by 3.5 mm (0.5%). That is within the usual ±3% guideline.

245/75R16265/70R16Difference (mm / revs)
Section width245 mm265 mm+20.0
Sidewall height183.8 mm185.5 mm+1.7
Rim diameter406.4 mm406.4 mm+0.0
Overall diameter773.9 mm777.4 mm+3.5
Circumference2,431.3 mm2,442.3 mm+11.0
Revolutions411 per km409 per km-2.0

Speedometer effect

With 265/70R16 fitted on a car calibrated for 245/75R16, the real speed when the speedometer shows:

Speedometer showsActual speed
50 km/h50.2 km/h
80 km/h80.4 km/h
100 km/h100.5 km/h
120 km/h120.5 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

245/75R16 dimensions · 265/70R16 dimensions · Open in calculator