Daysy fertility tracker

People who want to have a baby can use Daysy. The daily menstrual cycle is calculated using a proprietary algorithm and body temperature.

Many people use it for family planning. Some people are interested in using Daysy as an alternative to hormonal birth control or as a supplement to family planning tools, because of its cycle tracking capabilities.

If you are considering Daysy, here is what you need to know.

The small device called Daysy is used to track fertility. It uses your temperature to track when you are most fertile.

The small device takes your temperature each day and pairs with a free app where you can view information related to your fertility.


  • hormone-free.
  • It is easy to use.
  • Predicting ovulation helps.


  • Not designed for use as birth control.
  • Fertility tracking based on body temperature is not fool-proof.
  • must be used daily
  • Users experience technical difficulties.
  • It is less effective than traditional contraceptive methods.

People with a uterus and ovaries can use Daysy. People can use Daysy to learn more about their fertility.

If you want to have a baby, knowing when you are fertile may increase your chances.

While some people like using Daysy’s fertility tracking features as part of their natural birth control method, it’s designed for people who are trying to conceive.

You can make family planning decisions based on your fertility awareness. You are more likely to have a baby during your fertile window than on the days outside.

Daysy uses your basal body temperature and menstruation data to calculate when you’re more likely to conceive and when you’re less likely to conceive. Daysy takes your temperature using a precise sensor, stores your data, and calculates your fertility status.

The fertility status is signaled by the lights on the device.

  • You are more likely to have a baby if you are wearing red.
  • You are less likely to have a baby if you are green.
  • The predicted day of ovulation is indicated by red flashing lights.
  • Yellow lights can be an indicator of cycles.

It is easy to use, but it must be used every day. Consistency with daily measurements will make your results most accurate.

You will use Daysy first thing in the morning. It is recommended to get at least 3 to 4 hours of sleep before using Daysy.

To use Daysy.

  1. You can view your fertility status by pressing the activation button. Press it again to take your temperature.
  2. “Remove the protective cap and place the sensor under your tongue. Don’t do anything before this step, and lie down.”
  3. The device will sound when the measurement is recorded.

Recording your menstruation is part of Daysy. When you are on your period, press the activation button until the violet light appears and the device blinks once.

The learning phase will begin in the beginning. As Daysy learns more about your fertility, you will see a lot of yellow lights. The more you use Daysy, the more it learns about you.

Daysy is available to purchase on the company’s website,

It is also available on:

Daysy is rated highly on Trustpilot and Amazon. Customer reviews praise the company for good customer service and warranty. Many customers write about their positive experiences using Daysy to prevent or plan a pregnancy.

Stori Evans wrote that this was a great alternative if you were trying to avoid birth control. You get the hang of it after a while, but I am still learning about it. It has helped me learn more about my body.

The company has faulty products, a glitch in the app, and high prices, according to other reviews. Users report technical difficulties with the device.

“It never syncs with the app. You have to keep doing it until it works. Half the time it doesn’t save when I input information. It takes about 2 minutes for it to take your temperature.”

Users complain about the high number of yellow days, which can indicate fertile days or that Daysy is still learning. Reviewers mention that they became pregnant despite using the device. The device is not marketed for pregnancy prevention.

There are no physical side effects when using Daysy. It is as safe as a regular temperature. The FDA registered it.

Pricing Insurance coverage Main features
Daysy one-time fee of $299 may be reimbursed by some insurance plans and eligible for health savings account (HSA) and flexible savings account (FSA) funds powered by a self-learning algorithm to predict days of fertility and ovulation
Mira starts at $199 for the starter kit and $40.50 for a 20-pack of fertility wands eligible for HSA and FSA uses a device to analyze ovulation strips and relay personalized information about your fertility
Tempdrop Fertility and Ovulation Tracker one-time fee of $199 health insurance not accepted wearable sensor pairs with app

Fertility and family planning are complex, so there’s a wide variety of birth control methods out there. The best option for you depends on your goals, and there’s a possibility that Daysy may not be a fit for you. However, there are other natural birth control methods to consider.

“Tracking your cycle and taking your temperature is an alternative to daysy. Tracking and understanding the rise and fall of your body temperature can help you predict the days you’re fertile.”

If you want a budget-friendly option, you can do it yourself, but it is an option if you have trouble with the app.

If the fertility awareness associated with Daysy is what intrigues you, consider the rhythm method. This involves tracking your menstrual cycle and using the data to predict future cycles and gain a better awareness of your body.


Additionally, Phexxi is a newer nonhormonal birth control gel, available by prescription, that’s placed inside the vagina just before penis-in-vagina sex to reduce the risk of pregnancy. It works by preventing semen from changing the pH of the vagina.

Natural Cycles app

Natural Cycles, or NC, is an app designed for birth control and fertility awareness.

“The app uses the NC Thermometer and the app’s algorithm to calculate a user’s fertility status.”

It was first cleared for use as a contraceptive device in 2018 by the Food and Drug Administration (FDA).

It is easy to get started with Daysy.

You can download the app after ordering your tracker. You will need to charge the device before use. You need to charge it using the cable every 1 to 2 months.

“You don’t need to purchase anything else because Daysy comes with everything you need.”

If you are considering doing natural family planning, you can talk to a doctor or work with them. If you are taking any medications that affect your body temperature, you should consult with your doctor. This can affect the effectiveness of Daysy.

If you are using other forms of birth control, you should check if Daysy is compatible with your method. While on birth control, daysy should not be used.

How effective is Daysy?

Daysy claims to be 99.4 percent accurate. This was confirmed by a study funded by the company. In 2018, unaffiliated researchers found that Daysy wasn’t as accurate as the company claims, and the company’s article was retracted shortly after in 2018.

A new study funded by the company in 2020 also found the device to be 99.4 accurate in distinguishing fertile days from infertile days, and still stands.

Does insurance cover Daysy?

You may be able to get a portion of the cost reimbursed by your health insurance plan if you use Daysy as a form of payment.

It is also eligible for health savings accounts.

Is Daysy worth the money?

It is a one-time expense. It may be less expensive over time than other tracking devices.

It may be worth the money to you if you are looking for a natural family planning.

If you have health insurance, birth control medication may be covered completely, while IUDs can be considered cost effective, since they last for years and are very effective at preventing pregnancies.

Can you still get pregnant when you’re not ovulating or when you’re on your period?

Yes, you can still get pregnant on your period and outside of ovulation. You can also still get pregnant on birth control, though this is rare, and in other scenarios such as while breastfeeding.

“One option for tracking menstrual cycle and fertility is Daysy. If you are not trying to have a baby, we don’t recommend it as an alternative to hormonal contraception.”

There are many other birth control methods, from conventional condoms to other natural or nonhormonal birth control methods.

Lacey Muinos is a health, wellness, and beauty writer based in Southern California. She holds a BA in English. Her work has appeared in digital publications like Livestrong, Verywell, Business Insider, Eat This Not That, and others. When she’s not writing, Lacey is likely pursuing her other interests: skin care, plant-based cooking, Pilates, and traveling. You can keep up with her by visiting her website or her blog.