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Due date calculator

The calculator on this page can help you work out when you might expect your baby to arrive.

When was the first day of your last period?

For example, 15 4 2021

Some women's cycles are not exactly 28 days. Adjust the cycle length if your cycle is shorter or longer than 28 days.

Using the due date calculator

To find your due date, enter the date of the first day of your last period, and select 'show your due date'. Pregnancy normally lasts from 37 weeks to 42 weeks from the first day of your last period.

You need to know the first day of your last period to use this calculator. If you do not know it or are unsure, speak to a midwife or GP.

As part of your pregnancy (antenatal) care, your midwife will offer you a 12-week scan that may give you a more accurate date for the birth of your baby.

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Sign up for Start4Life's pregnancy and baby emails for expert advice, videos and tips on pregnancy, birth and beyond.

You can find pregnancy and baby apps and tools in the NHS apps library.

Unplanned or unsure? Find out Sexwise has more information and support.

Page last reviewed: 29 April 2021
Next review due: 29 April 2024