Hazel is a private period tracker and menstrual cycle calendar that keeps everything on your phone. No account, no cloud, no ads, and no analytics. What you log stays in the app, on your device, and you can prove it: turn on Airplane mode and Hazel keeps working, because it never needed a connection.
Most period tracking apps quietly send sensitive reproductive-health data to third parties. Hazel is built the opposite way. There is no sign-in, no server, and no tracking code anywhere in the app. "No data collected" is not a promise here. It is the architecture.
WHAT YOU CAN DO
- Log your period in a tap: spotting, light, medium, heavy, or none.
- Track symptoms, mood, PMS, cramps, and a private note for any day, so you keep a period diary you can look back through.
- See where you are at a glance: cycle day, current phase (menstrual, follicular, ovulation, luteal), and a period calendar of your history that reads as plain dates, not a colour code to decipher.
- Get honest period predictions. Hazel shows your next period as a range, not a false-precise single day, and the range widens or tightens based on how regular or irregular your cycles actually are.
- Estimate your fertile window and ovulation day with the built-in ovulation calendar, or turn fertility tracking off entirely if you would rather not see it.
- Set or correct your cycle start date with a simple in-app calendar.
PRIVATE BY DESIGN
- No account and no sign-in, ever. An anonymous period tracker in the plainest sense.
- Nothing leaves your phone unless you export it yourself.
- No ads, no trackers, no analytics, and no AI guessing about your body.
- No streaks and no pressure to log every day.
- Works fully offline. An offline period tracker that never needs the internet.
MADE TO FEEL CALM
Hazel is deliberately quiet. Warm, editorial design, a discreet app name that reveals nothing on your home screen, and microcopy with a voice, not the usual clinical or data-hungry period app. Choose from several colour themes, light and dark.
INSIGHTS
Once you have logged a cycle or two, Hazel shows your average cycle length, average period length, your cycle history, and how steady or irregular your cycles are.
HAZEL PLUS (optional, one-time)
Hazel is free and complete. You never have to pay to track your cycle. If you would like to support an app with no ads and no data-selling, a single one-time purchase unlocks Hazel Plus:
- Encrypted backups, locked with your own passphrase.
- Pattern insights: which symptoms cluster around your period, your mood patterns, and whether your cycle length is steadying.
- Small future touches, no upsells.
Prefer to give a little more? A second one-time option unlocks the same Plus at a higher price. And if you want to keep an ad-free, data-free app going, there is an optional small monthly thank-you. It unlocks nothing and gates nothing, and you can cancel it any time in Google Play.
YOUR DATA, YOUR CONTROL
Export a plain backup any time, or an encrypted one with Plus. Delete everything from the app whenever you want. There is no copy of your data anywhere else, because there is nowhere else.
WHO HAZEL IS FOR
Anyone who wants a simple period tracker, a menstrual cycle tracker, an ovulation calendar or a fertility tracker that respects privacy. If you have left another cycle app over data concerns and want a period log with no account, no subscription pressure and no data selling, Hazel was built for you. It suits regular and irregular cycles alike, and anyone tracking PMS, cramps, mood or spotting alongside their period.
A NOTE
Hazel describes what you log and estimates from it. It is not a contraceptive method and not medical advice. For questions about your health, talk to a clinician.