Honest about what it knows.
Your next period comes as a most likely day, with a range around it and how sure it is. It learns from every cycle you log, so you know what to plan around.
Estimated. Not a method of contraception.
Circa OVA. Know your rhythm.
A cycle tracker that learns your body one cycle at a time and shows you how sure it is. The more you log, the better it knows you.
- We never sell your information.
- No ads or analytics code runs on our pages or software.
Grounded in the evidence.
It starts from clinical guidelines and a study of more than 600,000 real cycles, then learns yours. Every number behind it is labelled with its source.
Sample cycle. Estimated. Not a method of contraception.
What's inside.
- Log a period in one tap. Add flow, mood or signals like LH tests and waking temperature when you want to.
- Your ovulation window, estimated, with a chance for each day.Estimated. Not a method of contraception.
- On the pill? Your pack becomes a ring, and the daily reminder reads only “Your daily reminder.”
- Patterns worth a conversation, each shown with the guideline behind it. It names patterns, never conditions.
- A one-page report for your doctor, built and printed on your own device.
For every stage.
From your first period to perimenopause. Through the pill, a new baby, breastfeeding and coming off the pill, the ranges widen when life does.
Opens with your phone's lock.
Turn it on once, and your fingerprint, face, pattern or phone code opens Circa OVA. Nothing to type. A private recovery phrase, yours alone, brings it back on a new phone.
Start yours.
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