Conception Date Calculator

First day of last menstrual period




Conception date – 25 day cycle:

Conception date – 26 day cycle:

Conception date – 27 day cycle:

Conception date – 28 day cycle:

Conception date – 29 day cycle:

Conception date – 30 day cycle:

Conception date – 31 day cycle:

Conception date – 32 day cycle:

Conception date – 33 day cycle:

Conception date – 34 day cycle:

Conception date – 35 day cycle:

Conception date – 36 day cycle:

Conception date – 37 day cycle:

Conception date – 38 day cycle:

Are you pregnant and curious to know when the conception actually happened? Then here is a tool which will help you know just that.

The conception date calculator works on a simple principle that ovulation and conception are related functions and they occur 14 days before the next menstruation period. In a 28-day menstrual cycle ovulation happens approximately on the 14th day and the 5-6 days period before and after ovulation is the time when conception is possible.

Step-By-Step Guide to Conception Date Calculator

Since the calculation is completely based on the menstruation cycle details, the only detail required would be the first day of the last menstrual period. Here is a step-by-step guide to conception date calculator:

  1. In the month bar choose the month of the last period using the drop box.
  2. Then input the day of that month when it occurred.
  3. In the last step choose the year when it occurred.
  4. Finally hit the ‘Calculate date of conception’ button.

The tool is very simple and allows for changing the details without having to refresh the screen.

If your menstrual cycle is longer than 28 days then the estimated conception date would be a few days before the actual conception date. To avoid this discrepancy, we have a sub-tool that will calculate your conception date based on the duration of your menstruation cycle.

Using this conception date calculator you can determine when your baby was actually conceived. This is very important for determining the expected date of delivery through the date method. The only other accurate way of determining this conception date is through sonography where the fetal measurements and other physical parameters will tell what stage of the pregnancy the baby is in.

So fill in the form and get ready to find out when your little one was conceived.