Predict your fertile window, ovulation day, and next period. Accurate ovulation tracker tool for pregnancy planning & fertility awareness.
Enter the first day of your last period and average cycle length to find your fertile days.
Our ovulation date calculator online uses the standard method: ovulation typically occurs 14 days before your next period. By entering your LMP and cycle length, we predict ovulation day. The fertile window includes the 5 days before ovulation + ovulation day — your best chance for conception. The tool also estimates your next period based on cycle length.
| LMP Date | Ovulation Date | Fertile Window | Next Period |
|---|---|---|---|
| March 1, 2025 | March 15, 2025 | March 10-15 | March 29, 2025 |
| April 10, 2025 | April 24, 2025 | April 19-24 | May 8, 2025 |
| May 5, 2025 | May 19, 2025 | May 14-19 | June 2, 2025 |
*For irregular cycles, the fertility window calculator provides an estimate; consult a specialist for personalized tracking.
Developed by fertility health advocates, our ovulation calculator online provides a reliable, private, and ad-friendly way to track your cycle. Whether you're trying to conceive or better understand your body, this tool offers accurate ovulation prediction based on standard medical guidelines. No data is stored, and it's 100% free. Trusted by thousands of women worldwide for cycle tracking and pregnancy planning.