Know your fertile days naturally. No hormones, no guesswork, no subscription.
Every morning, measure your basal body temperature in just 60 seconds. Daysy instantly tells you whether you're fertile or not, with over 99% accuracy, clinically proven over 40 years of research.
🔴 Red = fertile or possibly fertile
🟡 Yellow = fluctuating, possibly fertile
🟢 Green = not fertile
Is Daysy right for me?
Daysy is for you if you want to:
- Conceive and want to know your fertile window precisely
- Understand your cycle and body on a deeper level
- Ditch the pill and find a long-term, natural alternative
Common questions, answered
Is it really accurate if my cycle is irregular?
Yes. Daysy's algorithm learns your unique cycle over time, including irregular patterns.
What if I forget to measure one morning?
Daysy handles occasional missed measurements.
Is this a subscription?
No. Daysy is a one-time purchase. The DaysyDay app is free, with no ongoing fees or hidden costs.
What if I have trouble syncing Daysy?
If you experience issues syncing Daysy with the DaysyDay app, contact us. We offer ongoing and free support to our customers with syncing issues.
How should I care for Daysy's battery?
Follow the supplied instructions for charging and caring for your Daysy. If your device needs servicing, we can help. See our service fee page for the applicable service fee.
Is Daysy suitable for shift workers?
Yes. Just measure when you wake up after roughly 4 hours of sleep. Make sure you have slept continuously for at least the final hour immediately before measuring.
How long does it take for Daysy to know your unique cycle rhythm?
2-3 cycles.
Is Daysy just a thermometer?
No. With a basic basal thermometer, you measure your temperature and interpret the pattern yourself. Daysy measures your basal body temperature with a very precise sensor and uses your measurements and cycle history to calculate your fertility. You take the measurement; Daysy does the rest for you without you having to chart and interpret temperature changes by hand.
Have more questions? Visit our Daysy and Lady-Comp FAQ page for detailed answers.
What's included
- Daysy fertility tracker
- Free DaysyDay app (cycle calendar, temperature curve, fertility forecast, partner sharing)
- Protective travel case
- Micro USB charging cable
- Quick guide and user manual
Why thousands of women trust Daysy
- 99.4% accuracy, clinically validated (EMA and FDA approved)
- Science-based algorithm with 40+ years of research and development
- Hormone-free and non-invasive
- Made in Germany by a family-owned company
- Lifetime expert support by phone and email
- 2-year warranty
- Free shipping across Australia
- ZIP payment plan available
99% of Daysy users would recommend it to a friend.
"I stopped taking the pill after 13 years and Daysy was the best thing to help me learn how to tune into the natural rhythm of my cycle. I wanted something really accurate, especially because I wasn't ready to have a baby yet." —K. Daysy customer
Not sure whether Daysy or Lady-Comp is the better fit for you? Read our guide: Daysy or Lady-comp: which should you choose?
Our team will ship your order within 5 business days. The time it takes to receive your order depends on the shipping method chosen at checkout.
Please be mindful when selecting personal care and intimate products, as all sales of these items are final. Due to hygiene concerns, we cannot offer refunds, exchanges, or returns on sanitary products (such as menstrual cups and discs, pads, period underwear, and sterilisers).
