Trusted by over 250,000 customers

Trusted by 250,000 customers

Know Your Body. Love Your Cycle.

Fertility Tracking That Actually Gets You.

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Understand Your Cycle and Make Confident Choices.
Title

Your body’s been tracking your fertility all along. We just made it visible.

Track your cycle and symptoms

Understand your body better by monitoring fertility signs, patterns, and changes effortlessly.

Plan or prevent pregnancy

Know exactly when you're fertile with 99% accuracy, no hormones or guesswork.

Take control of your health

Get real insights into your cycle so you can make informed decisions every day.

Take Control of Your Fertility with An Easy, Natural, and Stress-Free Solution.

Daysy’s self-learning algorithm uses your body’s natural rhythm to predict ovulation with precision. By measuring your basal body temperature, it calculates when you’re fertile and when you’re not, leaving no room for mistakes. With data from 5 million menstrual cycles, you can trust that the results are accurate and personalized.

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Proven, Trusted, and Backed by Science

Confident Cycle Tracking.

“Daysy combines smart technology with a natural approach, making cycle tracking effortless and accurate."

“A fertility tracker that’s both science-backed and easy to use. No hormones, no hassle—just real, reliable insights."

"Sleek, smart, and stress-free—Daysy is redefining how women track their cycles with precision and style."

"Daysy takes the guesswork out of fertility tracking, offering 99% accuracy in a beautifully designed, user-friendly device."

Tracking Your Cycle Has Never Been Easier.

Daysy’s proven algorithm analyzes your basal body temperature every morning, giving you an accurate update on your fertility status each day. By learning your unique cycle rhythm, it calculates when you’re fertile and when you're not—without any complicated charts. With daily, personalized results, you’ll always know exactly where you are in your cycle.

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Hear Directly from Cyclers Like You.

Trusted by over 250,000 customers

"I always struggled to track my cycle because I’d forget to log things, but daysy makes it effortless. I take my temp in the morning, and it tells me exactly where I am.”

Emily R.

VERIFIED BUYER

For Tracking Her Cycle

“After years of dealing with birth control side effects, I wanted something natural. This gives me total clarity on my cycle without any pills or weird symptoms. It’s honestly been life-changing.”

Jasmine M.

VERIFIED BUYER

For Hormone-Free Birth Control

“My husband and I were trying for months with no luck, and I was getting frustrated. Daysy made it so much easier to understand my fertile days, and within three months, we got our positive test!”

Sophia D.

VERIFIED BUYER

For Planning Pregnancy

“At first, I wasn’t sure if I was using it right, but after a couple of weeks, it became part of my routine. Now, I trust it completely.”

Megan T.

VERIFIED BUYER

For Understanding Her Body Better

Plan or Prevent Pregnancy Naturally with Ease. 

Whether you’re trying to conceive or avoid pregnancy, Daysy helps you make informed decisions every day. By tracking your unique cycle rhythm and predicting your fertility status, it gives you clear, reliable insights into when you’re fertile and when you’re not. Start today and take control of your reproductive health naturally!

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“I started Stemba with one goal: to change the way women experience their health. Too often, women’s needs are ignored, and access to reliable, science-backed solutions is limited. That’s why Stemba is here.”

Victoria Hughes

Founder and CEO of STEMBA

How it works

As easy as 1, 2, 3 ... Only about 60 seconds per day!

Measure Temperature

When you wake up, you measure your temperature under your tongue.

Enter Menstruation

Enter if you have your menstruation.

See Fertility Status

Daysy evaluates your data and shows you if you are fertile or not.
Poster

Sync, Track, and Stay in Control.

Get real-time cycle insights at your fingertips. Download the app and take charge of your fertility anywhere, anytime.

Get on the AppStore

Get on Google play

About Stemba

" Stemba was created for women, by women. Inspired by the founder’s daughters, Stella and Amber, Stemba exists to give women and girls access to the health products and resources they need to thrive. In a world where reproductive health is often overlooked or misunderstood, Stemba is building a future where women can take control of their well-being—without shame, without barriers, and with the support they deserve."

Common questions

How accurate is Daysy in identifying your fertile window?

When used correctly, Daysy is over 99% accurate in pinpointing your fertile days by providing reliable red (fertile) and green (non-fertile) indications. This accuracy helps users plan conception effectively.

Can Daysy be used by women with irregular cycles or PCOS?

Yes. While women with irregular cycles or PCOS may experience a longer learning phase (with more yellow days), Daysy adapts to your individual cycle over time. In cases of significant irregularity, consulting a healthcare provider is advisable.

How is Daysy different from a standard thermometer or period-tracking app?

Unlike basic thermometers or calendar-based apps, Daysy combines a clinical-grade sensor with a proprietary algorithm. It automatically analyzes your BBT and provides immediate, easy-to-read fertility status signals—eliminating the need for manual charting and guesswork.

How does Daysy support conception planning?

Daysy accurately confirms ovulation through a measurable temperature shift. By clearly indicating your fertile window, it helps you identify the best days for conception, taking the guesswork out of the process.

What happens if I miss a day or have an erratic schedule?

Occasional missed measurements are accounted for by the algorithm, though consistent daily use is recommended for optimal accuracy. If your schedule is irregular, the app allows you to note any disturbances, which helps maintain reliable predictions.

Is Daysy safe to use, and are there any side effects?

Daysy is completely non-invasive and hormone-free. It uses biocompatible materials and has been rigorously tested as a medical device, ensuring safety and long-term usability without any side effects.

How long does shipping take?

Generally, Daysy will arrive in 2-4 business days.

How long does it take Daysy to reliably "learn" my cycle?

Generally, we say that the Daysy has a learning phase of 3 to 4 cycles. This does not mean, however, that you will not get any green lights (infertile days) during that time. 

 

Daysy will start out very conservatively and base your fertile window primarily on statistical data and statistically you could ovulate as early as day 11, causing Daysy to start your red (fertile) days around day 6 or 7 depending on how long your menstruation was. It will then stay red until ovulation has been confirmed, at which point it will change to green light indicating infertile. 

 

Over the course of the next several cycles, Daysy will begin to weigh your data more heavily against the statistical data and slowly narrow down and give less red days as it is able to pinpoint your individual fertile window.

How does Daysy work?

Daysy is programmed with a complex algorithm which evaluates your cycle by tracking your morning temperature (taken under the tongue) and knowing when you have your period. Daysy will then show you right away if you are currently fertile or not.

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Take Control of Your Cycle Today.

Get Daysy — 299.00 EUR

2-YEAR WARRANTY · LIFETIME SUPPORT

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