Your Cycle Details
Enter the first day of bleeding of your most recent period.
Count from the first day of one period to the first day of the next. Most cycles are 26–32 days.
How it works: Ovulation typically occurs 14 days into your cycle (cycle length − 14 days luteal phase). Your fertile window opens 5 days before ovulation when sperm can survive, and closes about 24 hours after the egg is released.
Ovulation Calculator — Frequently Asked Questions
Sources & Methodology
Last reviewed: October 17, 2026
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