36 Years Ago Developed by
Dr. Rechberg
Technology you can rely on
Daysy meets the requirements for a medical device. Precision and quality are our top priority.
Valley Electronics AG, based in Switzerland and manufacturer of Daysy, is certified according to EN ISO 13485. All procedures at Valley Electronics AG are regularly audited internally and externally.
Valley Electronics AG is registered with the FDA. The FDA inspects our Zurich office and our suppliers. Our quality management system is audited annually by an independent European Notified Body.
Daysy's Unique Internal Algorithm
Proof Through Science
The accuracy of Daysy's internal algorithm has been systematically tested. For the scientific study, 107,000 cycles (basal body temperature, menstrual input) of 5,328 women from Germany and Switzerland were evaluated over a period of 10 years.
Independently Assessed Result
99.4% accuracy
Your measurement is compared by the internal algorithm with fixed data from 5 million menstrual cycles of 500,000 women.
Daysy also learns from your previous cycles. For example, if you ovulate later than normal, your period may also be later. In short, the distribution between fertile and infertile days is carefully determined every day.
When calculating fertile (red) days, Daysy is 99.4% accurate.
For more information:
Publication of the study .
Fact Sheet Study .
International
In 40 Countries
Daysy is used in 40 countries worldwide.
View the list of countries.
Daysy around the World
Gain insight into what your body is currently showing and how your current cycle is progressing in real-time. You can see how the basal body temperature (BBT) is displayed and how ovulation is recognized. BBT temperatures are determined by the different hormones active during your cycle. This creates a difference between the temperatures before and after ovulation.