If any good driver keeps an eye on his speed, Waze regulars have generally noticed a difference between the km/h displayed on their counter and those shown by the application. But which one is telling the truth?
In reality the answer is not so simple. It is established that an automotive speedometer should never underestimate your actual speed. It is to have a margin of maneuver that the manufacturers overestimate it slightly, of the order of 5% of your real speed. In short, if you are really driving at 50 km/h, your car’s speedometer will probably indicate 53 to 55 km/h depending on the model, and for a real speed of 130 km/h on the motorway, some vehicles even announce 135 to 138 km/h on the dashboard.
Therefore, it is not uncommon to see the speedometer of the Waze application display a lower speed compared to the speedometer of your vehicle, which gives the driver the feeling of being able to press a little more on the pedal. However, Waze does not tell the exact truth even if it would come closer to it than your meter.
The application, adopted by more than 140 million monthly users worldwide and 40% of French motorists, indeed displays a speed linked to the GPS of your smartphone. This will give its position and it is then easy for a machine to calculate the speed of movement. Still, GPS is often less accurate in cities with narrow streets and tight turns. There is also a small lag time when you accelerate for Waze to display a speed, unlike your speedometer which tracks the progress of your acceleration.
It all depends on the road you are driving on.
Conversely, if you drive at a continuous speed of 80 km/h on a road or 130 km/h on a highway, for example, Waze will be able to display a more faithful speed, which is stable and easier to calculate. It is therefore necessary to exercise a certain vigilance, especially if you are used to driving while flirting with the authorized speed limits.
A speeding of 5 km / h can be enough to be flashed by a radar and receive a fine of 135 euros and the loss of a point on the driving license. When you look at your speed, if in doubt, it is better to stay on the slight overestimation announced by the counter on your dashboard.