Private by default
Calculations happen in your browser. We do not save or receive the dates you enter.
Free women’s health tools
Useful answers, without giving away your dates.
Calm, private calculators for planning around your cycle and pregnancy. Everything runs on this page—your entries are never saved or sent to us.
Choose a calculatorSeven simple tools
What would you like to estimate?
Use your own dates, get an instant result, then close the page. Nothing is stored.
01
Period calculator
Estimate your next six period dates from your recent cycle pattern.
Open calculator →02Ovulation calculator
Estimate a six-day fertile window and likely ovulation date.
Open calculator →03Pregnancy due date calculator
Estimate a due date from your last period or a known conception date.
Open calculator →04Pregnancy week calculator
See an estimated gestational week, day, trimester, and due date.
Open calculator →05Cycle length calculator
Average the days between recent period starts and see the range.
Open calculator →06Cycle phase calculator
Place a date in a simplified menstrual, follicular, ovulation, or luteal phase.
Open calculator →07IVF due date calculator
Estimate a due date from a day-3 or day-5 embryo transfer.
Open calculator →Made the Flowy way
Your body is not a certainty machine.
Clear about uncertainty
Results are estimates, with plain-language limits instead of false precision.
Grounded in guidance
Methods link to public guidance from established women’s-health organizations.
These tools provide educational estimates, not diagnosis, medical advice, or birth control. Contact a qualified healthcare professional about symptoms or concerns.