Pregnancy Calculator

From first day of your period to the first day of your next period. Ranges from: 22 to 44. Default = 28 Optional: Leave 28 if unsure.
Due Date
Estimated Fertility Window
thru
Estimated Conception Date
Estimated Gestational Age
This is not a diagnosis. The calculations that are provided are estimates based on averages.

 

How long is your cycle?

For women who have a 28 to 32-day menstrual cycles, ovulation can take place between days 11 through 21, but it will only occur on ONE of these days. Remember, this is just an average of days that ovulation could take place—every woman’s cycle is different.

Ovulation itself only lasts for 12-24 hours; that is how long an egg is available for fertilization.

Do you know your days of ovulation?

Use our free ovulation calendar as a guide to help you track your ovulation. Some people also refer to this as an ovulation calculator.

Find out a date for your next period and when you could possibly receive a positive pregnancy test.

Affordable and reliable early detection pregnancy tests and ovulation test kits can be purchased online from our corporate sponsor Fairhaven Health.

Since it is so difficult to pin down exactly which day a woman ovulates, we give you a 10-day window of when ovulation is most likely to occur.

If you are trying to conceive, APA suggests having intercourse every other day in this window. If you are trying to prevent pregnancy, avoid sex within this window and the 3-5 days before, or at least ensure you are using a condom consistently and correctly.