The Conception Calculator

Due on April Fools' Day: When Did You Conceive?

Due dates & conception. Updated . Calculated with the standard pregnancy dating method used by ACOG and the NHS.

A baby due on April Fools' Day (April 1) was most likely conceived around July 9 of the previous year.

Due dateApril 1
Most likely conception dateJuly 9
Likely conception windowJuly 6 – July 12
Estimated last periodJune 25

Only a small share of babies arrive on their exact due date, so a holiday due date is a target rather than a promise.

Use the conception date calculator for your exact dates.

Conception Date Calculator: Find the most likely conception date from your due date.

Open the calculator

This article is general information, not medical advice. Talk to a doctor or midwife about your own pregnancy or fertility.