The Daysy fertility tracker recognises, analyses, and accurately display a womans unique menstral cycle.

Daysy is not a replacement for contraception.


We support women who want to be in control of their own body. 

Meet Daysy

Your Personal Fertility Tracker


Daysy is a fertility tracker that uses the fertility awareness method (FAM) by learning & tracking your menstrual cycle.

Daysy tells you when you are in your fertile window and when not. During your fertile window you can choose to plan a pregnancy, during your infertile phase you can not. It’s your choice.

Daysy´s Algorithm distinguishes fertile from infertile days with an accuracy of more than 99%. Your fertility status will be displayed either as a red (you are fertile) or green (you are not fertile) light.

*Daysy is not a contraception. Daysy tells you when you are in your fertile window. During your fertile window you can choose to use a contraceptive, i.e. a barrier method like a condom. 

As easy as 1,2,3…

Only 30-60 seconds per day!

Achieve a higher awareness of your body with Daysy … just 3 easy steps within 30-60 seconds a day!

  1. Every morning when you wake up, measure your temperature under your tongue.

  2. Enter if you have your menstruation.

  3. Daysy evaluates your data and shows you if you are fertile or not in the next 24 hours.


You can count on Daysy!

Why is Daysy so reliable? The fact that Daysy can determine your fertile days with an accuracy of more than 99% is due to the extensive database. Based on 5 million menstrual cycles and an algorithm that draws on knowledge from more than 30 years of research including clinical studies, Daysy can give you reliable information about your menstrual cycle.

Daysy’s program relies on the Lady-Comp algorithm, which has a proven track record of over 28 years.

The fertility computer is programmed to accurately determine and display the time of ovulation in the female body by taking your daily basal body temperature.

  • Red = fertile
    On red days, you can plan for a baby.

  • Red blinking = day of ovulation.

  • Green = infertile.
    You are not fertile on green days.

  • Yellow = learning phase/cycle fluctuations
    On yellow days, Daysy becomes better acquainted with you. If pregnancy is out of the question for you right now, consider these days as red and use a barrier method of your choice.