Pregnancy tools
Ovulation Tracker and Fertile Window Calculator
Estimate an ovulation date and fertile window from the first day of the last period and usual cycle length.
Open ovulation trackerQuick answer
This tool estimates ovulation from cycle dates. Cycles vary, so it is useful for fertility awareness but should not be used as contraception.
Frequently asked questions
How is ovulation estimated?
The estimate uses the first day of the last period and the usual cycle length.
Can this prevent pregnancy?
No. Pregnancy can occur outside an estimated fertile window.
This tool is for education and does not replace individual medical advice or care.