Health Calculators
Ovulation calculator.
Estimate your ovulation date and 6-day fertile window from your cycle length. Not for contraception.
Cycle information
Your fertile window
Fill the form and press Calculate.
About this tool
Ovulation typically occurs ~14 days before your next period. The fertile window covers the 5 days leading up to ovulation plus ovulation day itself, since sperm can survive in the reproductive tract for up to 5 days.
Disclaimer
Estimates only. Ovulation timing varies cycle to cycle. Do not use this calculator as a method of contraception. For conception support, combine with ovulation predictor kits and discuss any concerns with your healthcare provider.