A private period tracker that tells you how sure it is.
Log in seconds, see where you are on the ring, and get predictions with an honest window instead of a falsely exact date. No account. No server. Your logs stay on your iPhone.
- No account
- No ads or tracking
- Light and dark
In the app, every period you log adds to what it knows. After 3 cycles it switches from population averages to your own pattern.
This is the card from the app, showing the example cycle on the ring.
Wind-down
What makes Cycle different
Most period apps want an account, show ads and give you a single confident date. Cycle does none of that.
Private by design
No account and no server of its own. What you log is saved on your iPhone and in your iPhone’s own backups. Apple Health sharing is optional, and Delete everything really deletes.
Honest about uncertainty
Every prediction comes with a window and how sure Cycle is, in plain words. If your cycles vary, the window gets wider instead of pretending to know the day.
No ads, no tracking
Cycle has no ads, analytics or tracking. Logging, the calendar and predictions need no payment. Cycle Pro is optional.
What you get
Four tabs: Today, Calendar, Insights and Ask. Quick to use on a hard day.
Today ring
See which day of your cycle it is, what phase you are in, and when your next period is expected, with how sure Cycle is in plain words.
Calendar
Logged days, predicted periods and your fertile estimate on one calendar. Tap any day to log or edit it. Backdate when you forget.
One-tap logging
Flow, pain, symptoms and mood in a few taps. A quick “Period started?” button shows up when it is due.
Insights
Your cycle lengths and averages, from your own logs. Cycle Pro adds symptom patterns that repeat, pain by cycle day, a heads-up before symptoms usually hit, and a doctor one-pager.
Ask
Ask a question like “is this normal?” and get a plain answer. With Cycle Pro, the answer is compared with your own logs. Cycle never diagnoses and points you to a doctor when something needs one.
Made to be discreet
Optional Face ID or passcode lock, a reminder with no health details in it, light and dark mode, and a delete button that really deletes.
No account. No server.
Cycle has no account system and no server of its own, and it has no ads, analytics or tracking. What you log is saved on your iPhone, and it is included in your iPhone’s own backups, which Apple manages.
You decide about the rest: Apple Health reading and saving are optional, and you can export everything as JSON or CSV, or delete it from Settings. The App Store privacy label says Data Not Collected.
Cycle Pro is optional
The basics need no payment. Pro adds deeper insights if you want them.
Prices in US dollars; your price may differ by country and taxes. Subscriptions renew automatically at the price shown unless cancelled at least 24 hours before the end of the current period, and are charged to your Apple ID. Manage or cancel in the Settings app › your name › Subscriptions. See the Terms of Service and Privacy Policy.
Questions
Is Cycle birth control?
No. Cycle’s fertile-window estimate is not a method of contraception, so please do not rely on it to prevent or plan a pregnancy.
Is the ring on this page my data?
No. It shows an example cycle so you can see how Cycle works. There is nothing to type and nothing is saved, and this page sets no cookies and loads no analytics or trackers. Your own ring lives in the app, on your iPhone.
Is the ring here the same as in the app?
It follows the same rules the app starts with: day 1 is the first day of a period, ovulation is estimated about 14 days before the next period (a population average, not a measurement), the fertile window is about six days, and the next-period window is about ±5 days while Cycle is still learning. On this page that window is also drawn as a faint arc outside the ring, which the app shows on its calendar instead. In the app it then learns from what you log, and after 3 cycles it uses your own pattern.
Where is my data?
On your iPhone, and in your iPhone’s backups if you use them. We do not have a copy, so we cannot read it, sell it or recover it. Export it from Settings if you want your own copy.
How accurate are the predictions?
They are estimates, and they get steadier after about three logged cycles. If your cycles vary, Cycle shows a wider window instead of a false exact date.
Can I import from Apple Health?
Yes, if you allow it. Cycle can read menstrual flow, spotting and some symptom records already in Apple Health, and can save the days you log there if you turn that on. You can change this any time in the Health settings.
How do I cancel or get a refund?
Apple handles subscriptions: Settings app › your name › Subscriptions › Cycle Pro. Refund requests go to reportaproblem.apple.com. More help is on the support page.
Cycle gives general information and describes patterns in the days you log. It does not diagnose or treat anything, it is not a medical device and it is not birth control. Talk to a doctor about health decisions. The ring on this page shows example data.
Your cycle, kept on your phone.
No account, no server, no ads. Just an honest ring that learns from what you log.
Get Cycle on the App Store