Period tracker
Private by design — encrypted with your PIN, only you can read it.
…
Cycle length–days on average
Period length–days on average
Regularity–log 2+ cycles
Mood
Last 60 daysPain by cycle day
Average of what you loggedSymptom map
How often each symptom shows up on each day of your cycle- Period
- Predicted
- Fertile window
- Ovulation (est.)
Reminders
A nudge two days before your period.
Join free for discreet email reminders.
Learn about your cycle
- Irregular periods: what's normal, what causes them, and when to worry
- Heavy menstrual bleeding: how much is too much, and what can help
- PCOS symptoms and signs: what to look for and how it's diagnosed
- Signs of endometriosis: symptoms to know and how to get a diagnosis
- Perimenopause symptoms: the early signs, when it starts and what helps
Backup & sync
Questions
Is this period tracker really private?
Yes. Your period and symptom data is saved in your browser on your device. If you're a member, it syncs automatically to your other devices — but it is encrypted on your device with a PIN only you know before it is uploaded, so TrustFem can't read it. We never see your PIN, and wrong guesses are limited.
Do I need an account or app?
No. It works straight away in your browser with no sign-up. You can add it to your home screen so it opens like an app, and it works offline. A free account adds automatic encrypted sync between your devices and for optional email reminders.
How does it predict my next period?
It averages the length of your recent cycles — from the first day of one period to the first day of the next — and adds that to your last period. The more periods you log, the better the estimate.
What do the symptoms show?
After a couple of cycles you'll see which symptoms tend to come in the days before your period, and you can print a summary for your doctor with your cycle lengths, heavy days, pain scores and notes.
Can I use the fertile window as contraception?
No. The fertile window is a rough estimate based on ovulation about 14 days before your next period. Cycles vary, so it isn't reliable as birth control.