Due Date Estimator

Calculate delivery dates based on conception or LMP.

Formula & Methodology

Due date = LMP + 280 days, or conception date + 266 days.

Worked Example

Conception on February 1 gives an estimated due date around October 29.

Frequently Asked Questions

What if I know my conception date?

Add 266 days to the conception date for an estimated due date, which is often more accurate than the LMP method.

How accurate is the estimate?

It is an estimate; most births occur within two weeks of the due date. First-trimester ultrasound improves accuracy.

Is this medical advice?

No. Confirm your due date with your healthcare provider, who may adjust it based on ultrasound.

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