Conception Date Calculator (Estimate)

This tool calculates the date of conception based on a date of birth. This gives you context of when the two parents must have been present together.

The calculator estimates that a pregnancy typically lasts 266 days. This isn’t exact but is based on known average intervals.

The estimated date helps if you are trying to identify a father based on other information such as residency data or military service.

Conception Date Calculator

Estimated Conception Date:

How It Works

By simply inputting a birth date, you can unveil the approximate day conception might have occurred.

The calculator subtracts 266 days from the birth date to give you the result. Why 266 days?

The general medical consensus is that human gestation (from conception to birth) typically lasts about 280 days from the first day of the last menstrual cycle. However, conception usually occurs about 14 days after this.

This is why our calculator estimates conception to be around 266 days (280 minus 14) before the birth date.

Related Links: More Date Calculators