You’d think that more of us would have figured out how to track our periods in adulthood. (All those middle school nightmares had to be good for something, right?) But the red tide can still be unpredictable, especially if you’re planning for an event several months in the future. And that’s if you’re lucky. Many people have irregular periods that show up whenever they want, plans be damned. 

Period apps can help make sense of the chaos by logging your cycle, symptoms, and sending reminders. We spent a whole menstrual cycle testing every nook and cranny of six period trackers, including privacy policies. Clue came out on top, thanks to its clean, useful interface and flexible privacy policies. 

Here’s the TL;DR on how the best period tracking apps stack up:

1. Clue (Top Pick)
2. Cycles (Best for Couples)
3. Life (Best No-Frills Budget Option)
4. Flo (Best Period Content and Community)
5. SpotOn
6. Eve by Glow

The Best Period Tracking App

Of all the period apps we tested, Clue gives the user the most control in their privacy policy. You can use it without creating an official account with your name, with very little difference in the overall experience. (The only real difference is that your information will disappear if you delete the app or replace your phone.) This doesn’t mean the app can’t ever be traced back to you, but it adds some protection. 

Clue also has one of the most intuitive interfaces and thorough symptom trackers, and it generally did a good job of assessing user preferences and allowing customization without being overly technical. The premium version allows you to see period predictions up to six months in advance and get an overview of recurring symptoms. 

To get started, Clue asks if you’re trying to follow a pregnancy or track a period, when your last period started, how long your average cycle is, when you were born, whether you use birth control (and what it is), and whether you want a reminder before your next period. You can skip some of these questions. The first page is the circle overview of your cycle. This illustration comes up a lot in period apps and is based on the Cycle Beads method. It tells you how many days until your next period and whether you’re potentially fertile or not.

From there, it’s easy to tab over to the calendar view, check an analysis of your cycle length, period length, and cycle variation, or look at your history, view period-related content, or quickly track symptoms. With the default setting, you can log how heavy your bleeding is, cramps, mood, sleep length, sexual activity, and energy levels. The app also lets you customize these questions and others it asks, such as cravings, digestive symptoms, or even the type of sanitary product you’re using. If it’s still missed something, you can add your own tag to track a symptom it doesn’t automatically cover, such as back pain. You can set up push notifications for a late period, PMS window, birth control, basal body temperature, or just nudge you to use the app.

I found the app mostly intuitive to use. One of my major complaints—and it’s common among period apps—was that the app will predict your period, but if you don’t actually confirm that you started bleeding, it doesn’t keep a record of that prediction. You also have to tell the app how much you were bleeding (light, medium, heavy, spotting) in order to log a period, which might be frustrating for users uninterested in that level of detail. Finally, Clue didn’t quite nail my period date—it was off by one day.

Where Clue shines most is in its privacy policy—at least based on what the app says. Clue says it does not share any health data, and that the data it does share is exclusively to better customize the app for you, further scientific research, and potentially find new users. (The latter factor gave it a “privacy not included” label in a Mozilla Foundation report on period tracking apps.) It also says you can opt out of each of these situations.

You can withdraw consent from all data processing by deleting your account, changing your privacy preferences, and/or unsubscribing from email communications. You may also ask Clue to delete your data entirely by emailing [email protected]. Clue says it will delete it within 30 days. Finally, you can also request your information so you know exactly what the app knows about you. 

That said, just because an app says privacy is their policy doesn’t mean they’re following it. Still, we think Clue is the most well-rounded of the apps we tested, all of which have somewhat-murky policies. 

What Is A Period Tracking App?

Period apps are a multi-use tool. Most involve making predictions about the length of your period, your date of ovulation, and the length of your cycle overall. Even the most basic ones help predict when your next period is coming—whether that’s to restock the bathroom cabinet with menstrual gear or tweak your summer vacation by a few days. 

For people with irregular periods, apps can help track when you do and don’t bleed so you have an accurate record for your doctor. And more advanced features can help to track physical, mental, and emotional symptoms that might be related to your menstrual cycle. 

“​​Patients often come to my office and tell me that they have irregular periods, but once they start tracking them with an app, they realize that they are often much more regular than they initially thought,” says Carolyn Ross, MD, a gynecologist and Stix’s resident expert on vaginal and reproductive health. “Conversely, if their cycles really are irregular, it is helpful to have as much information as possible. Maybe they are getting midcycle bleeding every month, or maybe their periods are only coming every 4-5 months. This is all useful information for the gynecologist to have in order to treat appropriately.”

Period apps can also help with tracking fertility, either to avoid or to encourage conception. (Though it shouldn’t be used as a sole method of birth control.) All the apps we tested had the ability to predict a likely ovulation date and fertile window. Many had the option to track other fertility markers, such as vaginal discharge or basal body temperature. 

Will Period Tracking Apps Keep My Data Safe?

One of the biggest criticisms of period apps has to do with data collection. Most apps from big tech companies collect a lot of data Association for Computing Machinery “Where You Go Matters: A Study on the Privacy Implications of Continuous Location Tracking” View Source by default, like the kind of device you’re on and other websites and apps you visit. This can be true with period tracking apps, too—they aren’t protected by the Health Insurance Portability and Accountability Act (HIPAA), which means it’s possible that the apps can share and sell your (de-identified) information. And when it comes to the sensitive information on these apps, which could indicate pregnancy, miscarriage, and more, it’s vital to keep it secure. 

18 period tracking and reproductive apps—including three we tested; Clue, Flo, and Eve by Glow—were slapped with a “privacy not included” label in a report by the Mozilla Foundation. (The three other apps we tested, Cycles, SpotOn, and Life, were not included in the research.) This means the apps provide insufficient information to users about how their data might be used and make it difficult to opt out of sharing information.

Flo told its users it would never disclose “cycles, pregnancy, symptoms notes and other information that is entered by you,” but the Federal Trade Commission (FTC) Federal Trade Commission “FTC Finalizes Order with Flo Health, a Fertility-Tracking App that Shared Sensitive Health Data with Facebook, Google, and Others” View Source found that to be untrue in 2020. The company had to settle with the FTC, who said Flo “passed on certain intimate health details of its users to marketing and analytics companies like Facebook and Google”—including for advertising purposes, as reported by The New York Times. No financial penalty was involved.

Clue sold user information such as birth dates and advertising IDs (which allows companies to track consumers across different platforms) to Facebook and Google, among others, according to a 2020 report from the Norwegian Consumer Council. At the time, Clue technically told users their information would be sold, but the Council noted that it was buried deep in its privacy policy and it was prohibitively difficult for users to opt out. Clue has since amended its privacy policies and states it will not sell user data, but still collects some data.

Should You Use a Period Tracking App In A Post-Roe World?

Period app data privacy became an even larger concern after the Supreme Court overturned Roe v. Wade in June 2022, allowing states to make abortion illegal and prompting some people to delete period tracking apps altogether. Data and health experts are concerned user data could be bought or subpoenaed and used as evidence that a person pursued an abortion. All the apps we tested have some kind of privacy policy (we looked into them!), and most offer ways to customize it. Still, not everyone wants to put their trust in a big tech company. If you’re looking for the best period tracking app that doesn’t sell data, you may be best without an app altogether. 

On the subject of big tech: Period apps aren’t the only type of data that can be weaponized against its users. Meta supplied Nebraska law enforcement with messages from its platform, allowing them to pursue charges against a woman who helped her daughter obtain an abortion. Online search histories and texts can also put users at risk. (Google says it will auto-delete visits to some medical facilities, including abortion clinics, from its search history.) If you want to make extra-sure your information stays with you, try not to put it online.

Are Period Tracking Apps Healthy?

It’s helpful to know what’s going on with your body, even if your periods are regular or you’re on a method of birth control that helps regulate your cycle. For people with irregular, painful, or otherwise tough periods, an app can help track symptoms and provide a better record for your doctor.

That said, you shouldn’t rely on period apps alone as a primary method of birth control. (At least one app, Clue, makes you acknowledge that before turning on ovulation predictors.) They may not provide enough customized information for accurate fertility tracking, either. In one small study of 10 apps and five profiles of women, the apps only accurately predicted the day of ovulation 8% of the time SAGE Journals “Period tracker applications: What menstrual cycle information are they giving women?” View Source . The apps may help you get in the fertility ballpark, but on their own, they’re not as accurate as other methods like ovulation tests.

Most importantly, a period app isn’t a stand-in gyno or fertility doctor.

“Period tracking apps can provide useful information about your health. They do not take the place of a gynecologist, though,” says Ross. “If you are having any problems with your period or wondering, ‘Is this normal?’ make an appointment with your gynecologist to discuss.”

How to Track Your Period Without an App

It’s totally possible to track your period without using an app. The best way to do it is with a planner, calendar, or notebook and simply mark the days you menstruate, taking note of the date it starts and how long it lasts. You can also write down any symptoms you experience. Once you’ve gone through a few menstrual cycles, you’ll gather enough data to have an idea of what your periods are typically like. Like using an app, this should allow you to anticipate your periods rather than being caught off-guard.

How We Picked the Best Period Tracking App

Meet Your Guinea Pig

I’m Colleen Stinchcombe, a health writer with work in SELF, Woman’s Day, and Health.com. I’ve been bleeding regularly since the tender age of 11, and logging my periods (usually well after their start date) for at least five years. If only the apps could make me stop forgetting menstrual products when I travel…

Our Testing Process

To find the best period app, I tested 5 different apps for one full menstrual cycle. I focused on apps that specialize in period tracking, although some could also be used to try to conceive or track a pregnancy. Where possible, I inputted period historical info for up to a year to give the apps more information to work with. I logged symptoms at least three times a week in each app, and wandered through every tab trying to glean useful info about how the apps work. I also read through their privacy policies to understand what the apps did with my data.

For more information on how we found the best period tracker apps, read the test notes. 

The Period Tracking App Buying Guide

Who should try a period tracking app?

Anyone who needs help keeping track of when their period comes and goes could benefit from a period app. The apps are useful to alert you of an upcoming period, and some, like Flo, use machine learning to try to flag potential health issues based on symptoms you log. However, all of the apps present real data privacy concerns, even if they have generous privacy policies. 

Which features matter most when choosing a period tracking app?

Know what you’re looking to get out of a period app. For instance, if you’re hoping to track a regular period, an irregular period, avoid pregnancy, or plan a pregnancy, certain apps may be more useful than others.

These basic questions may help for figure out which period tracking app is best for you:

• Will it keep my data private? With an app, your data will ultimately always be in the hands of a tech company. Do with that what you will. Still, many period tracking apps have policies outlining what they do with your information. Look for one with a privacy policy that says it won’t sell your data and lets you access it if needed. 
• Is it accurate? If your periods are relatively regular, over time, the app should be able to predict when your period starts and ends. 
• Is it easy to use? The app’s interface should have enough information to encourage education on the comings and goings of your menstrual cycle, but it shouldn’t be so cluttered that it’s difficult to use.
• Can I customize what I want to track? Periods are different depending on who’s having them! The app should allow you to track certain symptoms and hide others that don’t apply to you.
• Do I feel comfortable when I use the app? This part is subjective, but the interface and language used by the app should reflect what you want to see when you’re tracking your period. Some people might like more gendered, euphemistic language and emoji-style illustrations; others may want a more no-frills, neutral approach. You should be able to eyeball this with a glance at the app’s website. 

Other Period Tracking Apps To Consider

The main reason Cycle fell short of our top pick was because its privacy policy isn’t as flexible—it doesn’t let you pick and choose the information you provide. But the app does delete your information once you’ve deleted your account. It also allows you to use it without an account, which means your health information gets stored on your phone, rather than on its servers. However, the app’s main selling point—that you can share your cycle information with a partner (who presumably will be on ice cream acquisition duty)—is only available if you connect your account to your name.

Cycles also opens with a CycleBeads representation, but it has individual dots for days, so it’s clear where you are in the month. It’s quick to log symptoms for the day or tab over to a calendar. The insights section of the app gives you a preview of how you might feel over the coming days, an overview of symptoms you regularly log, and the ability to change which reminders you want to get. Like all but one app on this list, its prediction was off by one day. But even regular periods aren’t perfectly routine, and I wouldn’t knock its prediction for that reason.

Like Clue, Cycles also doesn’t keep your predicted period date by default. Unlike Clue, you can change this in the settings—a victory for the forgetful.

Life has been my go-to period app for years. Based on my years of experience with the app, it’s good at telling me when to expect my period. That said, the app started crashing toward the end of testing, and the privacy policy sent seriously mixed messages. When you’re being encouraged to buy its premium features, the app touts that it doesn’t sell private health data. But reading its actual privacy policy, the app makes it clear it collects and sells “personal data” and makes no distinction for sensitive health information—so it’s unclear where its lofty claims come from.

Anyway, when the app is not crashing, it’s very easy to use—you open a page and immediately see how many days until your period, and your expected ovulation date. That’s displayed again on the calendar page, where you can add a period. The symptoms are tucked away at the top, and you can go back and log all symptoms regardless of how long after you’re entering them. The app has always been within a day or two of correctly predicting my period, and when it’s off, I can usually find another culprit (like recent travel or over-the-top exercise.)

By default, the app sends a reminder when your period is supposed to start. The premium version allows you to set up reminders for upcoming periods, fertility windows, birth control, and other time-sensitive health needs, like prescription refills. And, yes, this app will remember when you were supposed to get your period—it doesn’t make you put it in yourself, so future predictions assume it happened until otherwise told. That’s great for people with regular periods, but probably not ideal for people with irregular ones.

Of all the apps we tried, Flo was one of the most cluttered with information. The default page features a calendar at the top, when your next period is starting, the ability to log a period, add symptoms, what day in your cycle you’re on, your estimated chance of getting pregnant, what Flo thinks your discharge will be like for the day, posts from its blog about sex, PMS, and vaginal odor, a breakdown of your typical cycle, cycle history, and cycle trends. That’s all before you tab over to any other sections, including a forum-like feed that feels like off-brand Facebook for period stuff.

The free version of the app gives you a pretty robust list of basics, like period prediction, ovulation prediction, tons of trackable symptoms, custom reminders, and health insights. The premium version creates a custom daily health prediction and gives you access to more of Flo’s content. It also lets you access its “health assistant”—though from what I could tell, it’s just an AI. Most of Flo’s article images were pretty feminine, though it had diverse representations of bodies and sexualities. For some reason, the default profile icon is… a dog.

Flo managed to predict my period start date more accurately (by one day) than the other apps, and it’s one of the few that claims to use machine learning. Like other apps on this list, you have to log your period on the day it starts or it will assume your cycle didn’t happen, though it auto-generates the rest of your bleeding days once you input the start date.

Flo has come under fire for misusing user data in the past. Perhaps because of this, it has one of the easiest-to-read privacy policy breakdowns in the user profile area. It says explicitly that it does not sell your data, and that it’s only used for further customization and will only share “anonymized data sets” for scientific purposes. Recently, Flo announced that its users can set an “Anonymous Mode,” which prevents Flo from being able to connect data to the person behind it. This feature launched after this round of testing, but we’ll try it out next time.

Period Tracking Apps You Can Skip

I wanted to love SpotOn. It’s the only app on this list that’s created by a health organization, Planned Parenthood. But the app is missing the je ne sais quois that makes others fun to use, with a distinct health insurance-type feel. It also had a few noticeable glitches. For example, the calendar wouldn’t predict my upcoming periods or fertile days after my first cycle with the app. (It was only off by one day during testing, but I had no idea when I was supposed to bleed next because it just… never told me.)

The app says it lets you start a chat with a health educator (a button auto-generates an SMS message) at any time. I tried it out and after asking for my age, gender, zip code, and race, it took about eight minutes for someone to respond. 

To its credit, SpotOn was the least gendered app of all the ones we tested. The privacy policy is limited, but it says it only shares data to improve the app. If the app got an update, we’d give it another look.

Eve by Glow is marketed as a sex-focused period app, though it didn’t ask any more questions about sexual activities than other apps. It also felt the most gendered of all the apps. It uses emojis to track symptoms and actions: “Sex drive” offered up options of red frilly panties for “do me now” (the app’s words, not mine) and large tan panties for “MIA” (not having sex).

How you feel about the tone of the app depends on your own preferences and sense of humor. To me, it ranged from vaguely funny to confusing and even obnoxious. To log sex, for example, the app lists phrases like “banana-free” (sex without a penis), “makeout sesh” (kissing), and “all me” (masturbation). Between that, and the fact that one of its premium features is a seven-day “forecast” of symptoms that tells you what to expect if you’re PMSing, ovulating, or on your period, I got a throwback to early-2000s teenage astrology books. That said, it was just as accurate as the other apps—only off by one day.

Like Flo, the app is cluttered. At the top of the default page is a cycle ring, a button to log the day, link to calendar, period analysis, period chart, and symptom forecast, and then a feed of polls, quizzes, vlogs, advice, videos, fact or fiction games, stories, forums, and more. It feels like a community conversation spot first, period tracker second. Another big bummer: you can’t log symptoms for previous days.

One thing that was cool is that approaching my period, it told me what percentage of other period-havers were feeling extra tired, had acne, felt happy, or had cramps. Solidarity. As far as Eve by Glow’s privacy policy, it says that any data sold is anonymized.

Our research and review process is intended for informational purposes only—never as a substitute for medical treatment, diagnosis, or advice. Recommendations or information found on this site do not infer a doctor-patient relationship. Always consult a healthcare provider if you have questions about how a product, service, or intervention may impact your individual physical or mental health. Our evaluations of products, services, and interventions have not been reviewed by the Food and Drug Administration. Information and research about health changes frequently. Therefore, some details or advice on this site may not be up-to-date with current recommendations. The Nessie is an independent publication and is not in any way affiliated with the production or creation of products, providers, services, or interventions featured in reviews or articles on the site.