Best Period Tracker Apps in 2026

Flo is the most downloaded period tracker in the world, with over 420 million total downloads. The prediction algorithms are among the most accurate available — after a few cycles of data, most users report period predictions within 1-2 days of accuracy. The AI assistant provides personalized health insights based on your logged symptoms, mood, and cycle data.

Beyond basic period tracking, Flo covers the full spectrum: ovulation estimation, PMS symptom tracking, sexual activity logging, mood patterns, and a massive library of medically-reviewed health content. When you’re ready to switch to pregnancy mode, Flo tends to transition pretty smoothly. Flo includes week-by-week tracking and pregnancy content.

Privacy has been a concern. Flo settled with the FTC in 2021 over data sharing practices. Since then, they’ve introduced Anonymous Mode. Anonymous Mode lets you use the app without connecting personal identifying information. It’s a real improvement, but some users are still cautious. Premium is needed for many advanced features, and the free experience includes ads.

Clue is the period tracker for people who value science and privacy over social features. The interface is deliberately clinical. There are no pink flowers and no euphemisms. It tracks your cycle with data-first precision. It also publishes peer-reviewed research based on aggregate user data. The science credentials are genuine.

Clue stores data in the EU under GDPR protection. Clue has been transparent about not selling personal data. For women in places where reproductive health data privacy is a real concern, Clue’s European data jurisdiction and clear privacy stance matter. The free tier is genuinely useful — no ads, functional tracking, and cycle predictions.

Clue Plus (premium) adds more detailed analysis, fertility predictions, and historical pattern insights. The editorial content is evidence-based but smaller in volume than Flo's library. Clue doesn't include a pregnancy mode — if you conceive, you'll need to switch to a different app for pregnancy tracking.

Natural Cycles is different because it's the first and only FDA-cleared app for use as birth control. It uses basal body temperature (BBT) readings — taken each morning before getting out of bed — to determine which days you're fertile and which days you're not. It's a fundamentally different approach from algorithm-only trackers.

The temperature data makes Natural Cycles significantly more accurate than period trackers that rely solely on cycle length history. It tells you with a green day (not fertile) or red day (fertile/use protection) status. For women trying to conceive, the same data identifies your fertile window with high precision.

But the trade-off is that you have to be disciplined about it. You need to take your temperature at the same time every morning. You need to use it consistently. Alcohol, illness, and disrupted sleep affect BBT readings. The subscription cost includes access to a thermometer. This isn't a casual period tracker — it's a commitment to temperature-based fertility awareness. If you're willing to commit, the data quality is superior to any algorithm-only app.

Ovia Fertility is a period and fertility tracker made for women who are trying to conceive. While it handles basic period tracking, its real strength is the fertile window predictions, ovulation estimates, and TTC-specific insights. The app logs more health data points than most competitors — cervical mucus, BBT, OPK results, and intercourse timing.

Ovia is often available free through employer health benefits programs. If your company offers Ovia as part of its wellness benefits, you already have access. The fertility-focused features help you spot patterns that can affect your chances of conceiving.

Privacy is usually the main concern. The employer-sponsored model means your health data contributes to aggregate reports. Ovia has updated its privacy practices. But employer-subsidized fertility tracking still raises questions worth thinking about. If privacy is your top concern, Clue or Natural Cycles is probably a better pick.