ovuLivo began with a simple observation: the fertile six days matter, but the peak two matter more — and working them out by hand is fiddly and easy to confuse.
What the tool does
Enter the first day of your last period and your average cycle length. The calculator estimates your ovulation day, shows your fertile window and the two most fertile days, and draws the whole thing on a cycle calendar. A temperature log lets you confirm when ovulation actually happened.
Why it runs in your browser
Every calculation happens locally on your device. Your dates and temperatures never leave your computer. No account, no server-side storage, nothing to install — and the tool stays free.
What it does not do
Predictions are estimates. They are not contraception and not a substitute for medical care. For irregular cycles, early-stage fertility concerns, or any worry, talk to a healthcare professional — and use our guides to interpret what your body is showing you.
Questions or feedback? See the contact page. For what little we store, read the privacy policy.