The principle of using trackle is that you wear it while you sleep. That means, trackle is particularly convenient for women with restless sleep, mothers with children or women who work shifts, because it doesn’t matter when you sleep. 

In general, a basal body temperature can be calculated when you have slept for 4 hours. 


This is how it works: trackle measures your core body temperature once every minute from the time you insert it. This results in a very long series of measurements that covers the entire time you wear the sensor. To determine the basal value, however, the warm-up and cool-down phases of the sensor are cut off from the respective series of measurements. 


After the transmission, you receive the lowest value of the night – your basal value – in your app.  This value is calculated from the long series of measurements and is the most reliable way to tell whether you ovulated or not. 


Theoretically, it is possible to have cases where the different time of day or length of sleep impacts the measured value – but that isn’t necessarily the case with every woman. If this happens, you can enter an interfering factor in the trackle app for that day – that way the value is excluded and not taken into account for evaluation. 


If you want to learn more about “interfering factors”, please also see here:

What are “interfering factors”?