pregnancy due date calculator

Use our pregnancy due date calculator to instantly calculate your pregnancy due date. Plus our comprehensive guide to what you need to do next - who to see, when to see them and how to arrange those important antenatal tests and scans.

Calculate your due date

How is your due date calculated using this pregnancy calendar?

Did you know that on the day your baby is conceived you are already two weeks pregnant??!! It doesn't sound right but that's how gestational weeks are calculated.

Most pregnancies last 40 weeks (38 weeks from the actual conception date).

Basically, the start date of your pregnancy is actually the first day of your last period - Day 1 of your menstrual cycle. So if you have a regular 28-day cycle you'll ovulate around Day 14 and your baby will be conceived around that date, the start of gestational Week 3.

This means, that by the end of the third gestational week your baby will be one week old, but you're already at the end of Week 3 of your pregnancy.

This is how your pregnancy health care provider will calculate your due date. If you have irregular cycles you can ask about a 'dating scan' an ultrasound done around the six-week mark, which calculates the due date based on embryo size.

Remember though, that only about 5 per cent of babies arrive on their due date. It is quite normal for a baby to arrive a week or two early or late.

So when you using an online pregnancy due date calculator, please remember that online pregnancy calculators can only provide an estimate of your due date, and that a due date calculated by your health care provider is the best date to use.