The Conception Calculator

Due on Boxing 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 Boxing Day (December 26) was most likely conceived around April 4 of the previous year.

Due dateDecember 26
Most likely conception dateApril 4
Likely conception windowApril 1 – April 7
Estimated last periodMarch 21

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.

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