🌸 Ovulation Calculator
Enter your last period start date and average cycle length
How Does the Ovulation Calculator Work?
Ovulation typically occurs about 14 days before the start of your next period. Our ovulation calculator uses your last period date and average cycle length to estimate when you'll ovulate. Your fertile window — the days when pregnancy is most likely — is usually 5 days before ovulation through the day of ovulation.
For a 28-day cycle, ovulation typically happens around day 14. For longer cycles, ovulation occurs later. For shorter cycles, it occurs earlier. Tracking your cycle over several months gives you the most accurate picture of your personal patterns.
Remember that cycle length can vary from month to month due to stress, illness, diet, and other factors. This calculator provides estimates only — not medical guidance. If you are trying to conceive or have concerns about your cycle, please speak with your OB-GYN or reproductive health provider.