Ovulation & Cycle Tracker
Calculate your fertile window, ovulation date, period dates, and cycle phases for up to 6 future cycles. All calculations run entirely in your browser — no data is sent to any server.
Typical: 21–35 days
Cycle Predictions
→ Thu Jun 18, 2026
→ Mon Jun 29, 2026
→ Thu Jul 16, 2026
→ Mon Jul 27, 2026
→ Thu Aug 13, 2026
→ Mon Aug 24, 2026
How to read your results
The fertile window is the 5 days before ovulation plus ovulation day — when pregnancy is possible. These are estimates based on average cycle patterns. Actual ovulation can vary by several days due to stress, illness, or hormonal changes. Use ovulation test strips for precision.
How it works
This ovulation & cycle tracker runs entirely in your browser — no data is sent to any server. Simply fill in the fields above and the result updates instantly. You can copy the output with the copy button provided.
Frequently Asked Questions
How is the fertile window calculated?
Ovulation typically occurs 14 days before the next period. The fertile window is the 5 days before ovulation plus ovulation day itself.
Is this data stored anywhere?
No. All calculations are done in JavaScript in your browser. Nothing is sent to a server or shared with any third party.