Ranking · Period trackers
The 5 Best Period Tracker Apps of 2026
Predictions, symptom logging and FDA-cleared birth control, with a plain account of what each app does with your data.
A period tracker can help you see your next period coming, spot patterns in your symptoms and have better conversations with your clinician. Our top pick is Flo, one of the most widely used trackers and the one with the most features: predictions, detailed symptom logging and a free Anonymous Mode. Clue is the science-forward alternative, and the one we’d choose if privacy comes first. Natural Cycles is a different class of app: FDA-cleared birth control based on your temperature. Period Tracker and Stardust are simpler options.
Period data is sensitive, and these apps handle it very differently, so we set out each one’s privacy record plainly below. And unless an app is cleared as birth control, its “safe days” aren’t contraception. Prices are as of November 2026.
Our picks at a glance
Period trackers
- Best overallFlo4.1/5
- Best if privacy comes firstClue4.1/5
- Best simple calendarPeriod Tracker (GP Apps)3.6/5
- Most social; check its privacy firstStardust3.2/5
FDA-cleared birth control
- Best for hormone-free birth controlNatural Cycles4.0/5
Compare the apps side by side
| App | Our score | Price | Platforms | How it works | Free tier |
|---|---|---|---|---|---|
| Flo | 4.1 | Free; Premium plans listed up to $59.99 | iOS, Android, Apple Watch, Wear OS | Cycle and symptom logging, with period and ovulation predictions | Yes: predictions, symptom logging and Anonymous Mode |
| Clue | 4.1 | Free; Clue Plus $39.99/yr | iPhone, Android | Cycle and symptom logging, with predictions; imports wearable data | Yes: cycle tracking and predictions |
| Period Tracker (GP Apps) | 3.6 | Free with ads; membership $9.99/yr | iOS, Android, Apple Watch | A period calendar with predictions; entries stay on your phone unless you back up | Yes, with ads |
| Stardust | 3.2 | Free; Premium $6.99/mo or $24.99–$39.99/yr | iPhone, Android | Cycle predictions, with syncing to a partner or friends | Yes; the free and paid split isn’t clearly listed |
| Natural Cycles | 4.0 | $149.99/yr or $21.99/mo | iOS, Android, Apple Watch | Overnight temperature from its band, an Oura ring, Apple Watch, Garmin or WHOOP | No |
Predictions are estimates. Period and fertile-window predictions come from what you log (and, for Natural Cycles, your temperature). Natural Cycles is the only app here sold as FDA-cleared birth control; for the others, a “low chance” day isn’t contraception. We haven’t tested any app’s predictions ourselves.
Period trackers
Flo
- Not measured
- Platforms: iOS, Android, Apple Watch, Wear OS
- Price: Free; Premium plans listed up to $59.99
Flo is one of the most widely used period trackers, with more than 100 million downloads on Google Play alone, and it has the most features here. The free version predicts your period and ovulation, logs symptoms and includes Anonymous Mode; Premium adds a health-assistant chatbot, cycle trends and a report for your doctor. It runs on iPhone, Android, Apple Watch and Wear OS.
Read the privacy section before you start, and if you use Flo, turn on Anonymous Mode. The App Store lists Premium plans up to $59.99 without saying which billing period each covers.
Pros of Flo
- Most features of the trackers here
- Free predictions, symptom logging and Anonymous Mode
- iPhone, Android, Apple Watch and Wear OS
Cons of Flo
- 2021 FTC settlement over sharing health data
- Many features need Premium
- Premium pricing isn’t clearly published
Clue
- Not measured
- Platforms: iPhone, Android
- Price: Free; Clue Plus $39.99/yr
Clue is the science-forward choice, and the one we’d pick if privacy comes first. It’s based in Berlin, covered by the EU’s data-protection law (GDPR) and stores data on servers in the EU. The free version covers cycle tracking and predictions. Clue Plus, $39.99 a year, adds longer-range predictions, temperature charts, modes for trying to conceive, pregnancy and perimenopause, and partner sharing.
The Clue app isn’t birth control. An FDA-cleared contraceptive feature was cleared in 2021 but never launched, and the app now says it isn’t intended for contraception.
Pros of Clue
- EU privacy law and EU servers
- Science-based content
- Clue Plus is $39.99/yr
Cons of Clue
- Extra modes need Clue Plus
- Some app events still go to ad networks
- Not birth control
Period Tracker (GP Apps)
- Not measured
- Platforms: iOS, Android, Apple Watch
- Price: Free with ads; membership $9.99/yr
If you want a calendar that predicts your next period and little else, Period Tracker by GP Apps does that, free with ads, with an optional $9.99-a-year membership. It runs on iPhone, Apple Watch and Android, and your entries stay on your phone unless you set up an online backup. On Android, Simple Design’s Period Calendar is a bigger app in the same style.
Pros of Period Tracker (GP Apps)
- Simple and free
- Entries stay on your phone unless you back up
Cons of Period Tracker (GP Apps)
- Free version shows ads that use tracking identifiers
- Few features
Stardust
- Not measured
- Platforms: iPhone, Android
- Price: Free; Premium $6.99/mo or $24.99–$39.99/yr
Stardust’s draw is social: you can sync your cycle with a partner or friends, alongside moon and zodiac content. Premium is $6.99 a month, or $24.99 to $39.99 a year.
Its recent privacy record is the weakest of the apps here. In a July 2026 test, the Mozilla Foundation found it sending details such as birth-control type and symptoms to an analytics firm. Read the privacy section before you sign up.
Pros of Stardust
- Sync your cycle with a partner or friends
Cons of Stardust
- Weakest recent privacy record here
- Astrology content mixed with health tracking
- Its app-store privacy disclosures contradict each other
FDA-cleared birth control
Natural Cycles
- Not measured
- Platforms: iOS, Android, Apple Watch
- Price: $149.99/yr or $21.99/mo
Natural Cycles is a different class of app: an FDA-cleared contraceptive. It combines your period dates with your overnight temperature, from its own band (included with the annual plan), an Oura ring, an Apple Watch with a temperature sensor, Garmin or WHOOP, and tells you each day whether you need protection. Its label puts effectiveness at 93% with typical use and 98% when used exactly as intended.
It costs $149.99 a year, with no free tier, and it works only if you keep up the readings and abstain or use protection on fertile days. It also has modes for planning a pregnancy, pregnancy, postpartum and perimenopause.
Pros of Natural Cycles
- FDA-cleared birth control without hormones
- Works with its band, Oura, Apple Watch, Garmin or WHOOP
- Modes for planning a pregnancy and perimenopause
Cons of Natural Cycles
- $149.99/yr, with no free tier
- About 7 in 100 typical users get pregnant in a year
- Needs nightly temperature data and protection on fertile days
Your cycle data and privacy
Period data can reveal a pregnancy, a pregnancy loss or a missed period, and in the US, HIPAA, the federal health-privacy law, generally doesn’t cover apps you download yourself. Here’s each app’s record, plainly:
- Flo settled FTC charges in 2021 that it shared users’ health data with analytics services, including Facebook’s and Google’s, after promising not to. In a 2025 class action, Flo agreed to pay $8 million, and a jury found Meta had violated California privacy law by collecting Flo users’ data. Flo now says it doesn’t share health data for marketing, its free Anonymous Mode drops your name, email and ad ID, and a 2026 Mozilla test saw no health data reach ad partners.
- Clue says health data is never shared with or sold to advertisers, though basic app events, such as installs, go to ad networks. It has said publicly that it won’t comply with US subpoenas for user data; that pledge isn’t in its privacy policy.
- Natural Cycles says it never sells personal data and will contest law-enforcement requests where it has grounds. Its Go Anonymous setting, it says, stops even the company from linking your data to you.
- Period Tracker keeps entries on your phone unless you back up; Apple’s privacy label says identifiers and usage data are used to track you.
- Stardust withdrew a misleading end-to-end encryption claim in 2022, and Mozilla’s 2026 test found it sending health details to an analytics firm, which Stardust says is contractually barred from using them for its own purposes.
Whichever app you use, turn on anonymous or on-device modes where they exist, and switch off optional sharing and backups you don’t need.
How to choose
Decide what you need the app to do:
- The most features: Flo, with Anonymous Mode on.
- Privacy first: Clue, or a simple tracker that keeps entries on your phone.
- Hormone-free birth control: Natural Cycles, the only app here sold as FDA-cleared contraception. Ask your clinician whether it suits you.
- Just a calendar: Period Tracker.
- Tracking with friends: Stardust, once you’ve read its privacy record.
Whatever you choose, check its privacy settings on the first day, before you’ve logged anything sensitive.
How we tested
We haven’t lab-measured period tracker apps, so this ranking doesn’t rest on a measurement, and every app in it carries a “Not measured” label. We compared the apps on the features that matter for the job, what each free tier includes, what the paid plans cost and each app’s consensus standing: what independent reviewers and, where it exists, published research say about it. We checked every price against the app’s own plan pages and store listings in November 2026.
How we ranked: cycle and symptom tracking first, then free tier and price, with each app’s privacy record weighed into its score. Flo and Clue share a score; Flo leads on features and Clue on privacy. Natural Cycles is listed separately because it’s a regulated contraceptive, not a period tracker in the usual sense.
Frequently asked questions
What is the best period tracker app?
For most people, Flo: it has the most features, and its free version covers predictions and symptom logging. If privacy matters most, Clue. For birth control, Natural Cycles is the only app here sold as FDA-cleared contraception.
Is Flo safe to use?
Flo settled FTC charges in 2021 over sharing health data with analytics firms. It now says it doesn’t share health data for marketing, and a 2026 Mozilla test found none reaching ad partners. If you use Flo, turn on its free Anonymous Mode.
Can a period tracker app be used as birth control?
Only if it’s cleared for that use. Natural Cycles is FDA-cleared, with 93% effectiveness in typical use. The other apps here aren’t contraception, so don’t rely on their “low chance” days to prevent pregnancy.
Does HIPAA protect my period tracker data?
Generally not. US health officials say HIPAA usually doesn’t protect health information in apps you download yourself, unless the app comes from your doctor, your insurer or a company working for them. Some states, including Washington and California, have added their own protections.
Prices as of November 2026. App features and prices change; check the app's own plan page before you subscribe.