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Pregnancy test

Use our simple pregnancy due date calculator to estimate your baby's arrival date. Enter your information below to find out when you could give birth.

When you find out you're pregnant, one of the first things you'll probably wonder is 'when will my baby be born?'. Our due date calculator will give you an approximate date for the arrival of your baby.

How do you calculate your due date?

Your pregnancy due date is calculated from the first day of your last period, and it's assumed you conceived halfway between periods. If you conceived earlier or later in your cycle then this will probably effect your due date.

How accurate is a due date?

Only about four percent of babies are born on their due date. To give you a more accurate baby due date, your midwife will offer you a dating scan as part of your antenatal care. See our article on overdue babies for more on the accuracy of due dates.

Due date calculator

So if you're ready to estimate your due date, select the date of the first day of your last period and the normal length of your period in the NHS pregnancy calculator, then click on Calculate.  


What next now I know how many weeks pregnant I am?

You could look at when and how to book your first appointment with a midwife and what to expect in our article What a midwife does and other FAQs.

Now's the ideal time to sign up for our free Pregnancy & Baby newsletter. Our weekly email update delivers expert information about what to expect when, your baby's development and your health and well-being, right to your in-box.

What will happen during my pregnancy?

No two pregnancies are exactly the same - the average is between 37 and 42 weeks long, with important changes along the way. Your emotions might change as well.

Naturally you've got lots of questions. Take a look at our information on being pregnant, where you will find essential, evidenced-based information designed to help you make the best decisions for you and your baby.


Page last updated: 6 September 2016


Further information

Our support line offers practical and emotional support with feeding your baby and general enquiries for parents, members and volunteers: 0300 330 0700.

We also offer antenatal courses which are a great way to find out more about birth, labour and life with a new baby.

Make friends with other parents-to-be and new parents in your local area for support and friendship by seeing what NCT activities are happening nearby.

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