What is it?
The Ovulation Calculator estimates your Ovulation day (about), your Most fertile days and when your Next period may start, for the next few cycles.
Who is it for?
Couples trying to conceive and women tracking their cycle.
How to use it
Enter the First day of your last period and your Cycle length (from the first day of one period to the first day of the next). The answer appears as you type; there is no Calculate button. Tap Copy result to copy it, or Share on WhatsApp to send it.
How it works
Ovulation usually happens about 14 days before the next period. The fertile window is the 5 days before ovulation plus the day itself, because sperm can live up to 5 days.
Better accuracy
- Track cycle length for 3–6 months and use your average.
- Ovulation test kits (LH strips), cervical mucus changes and basal body temperature show your actual ovulation.
- Stress, illness, travel and PCOS can shift or skip ovulation.
Important
An estimate from the calendar method. Cycles vary; it is not a method of birth control. If you’ve been trying to conceive for 12 months (6 months if over 35) without success, see a doctor.
This is general information to help you understand your numbers, not medical advice. Talk to a doctor about your own health.
Errors and how to fix them
- “Choose a date”: enter the first day of your last period.
- Irregular cycles: predictions are less reliable; use ovulation kits.
Open the tool: Ovulation Calculator
Still stuck?
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Questions, or an error not listed here?
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