Ovulation Calculator — Fertile Window & Next Period Predictor
Find your fertile window and ovulation date from last period date
days
Frequently Asked Questions
Ovulation typically occurs 14 days before your next period. Formula: Ovulation Date = First day of last period + (Cycle length − 14). For 28-day cycle: Day 14. For 32-day cycle: Day 18.
The fertile window is 5 days before ovulation + the day of ovulation = 6 days total. Sperm can survive 3-5 days inside the reproductive tract. The most fertile days are 2 days before and the day of ovulation.