Baby Tools › Conception Date Calculator

Conception Date Calculator

Work backwards to estimate the day you most likely conceived.

This tool is for general information only and is not medical advice. Always talk to your doctor or midwife about your pregnancy and your baby.

How it works

1Choose what you know: due date, last period or birth date.

2Enter the date.

3See your estimated conception window.

How is the conception date estimated?

Conception usually happens about 266 days before the due date, or roughly two weeks after the first day of your last period.

Can it tell me the exact day?

No. It gives a likely window of a few days around ovulation, not an exact day.