Women’s Health Calculators
Pregnancy, ovulation, and cycle calculators designed to give you clear estimates for the moments that matter.
Which calculator do I need?
Start with where you are in the journey. If you are trying to conceive, the Ovulation Calculator estimates your fertile window from the first day of your last period and your average cycle length — the five days before ovulation plus ovulation day itself are when conception is most likely.
Once you have a positive test, the Pregnancy Due Date Calculator turns your last period date into an estimated due date using the standard 280-day rule and maps out trimester milestones along the way.
The OB Dating / Gestational Age Calculator is the clinical workhorse: it computes how many weeks and days along a pregnancy is from LMP, EDD, or ultrasound measurements, compares dating methods side by side, and applies the redating rules obstetric providers follow. Nursing students use it for charting practice; expectant parents use it to understand what the numbers from an appointment actually mean.
All three tools are educational. Cycle lengths vary, ultrasound dating has margins of error, and only your own clinician can confirm dates for medical decisions.