Due Date Calculator

When is my baby due?

The average pregnancy lasts 280 days (40 weeks) from the first day of your last menstrual period (LMP). This Due Date Calculator helps you estimate your delivery date using the same methods as doctors and midwives.

How We Calculate Due Date

• Last Period (LMP): The most common method. We add 280 days to the start of your last period. If your cycle is longer or shorter than 28 days, we adjust the calculation accordingly.
• Conception Date: If you know exactly when you conceived, we add 266 days (38 weeks) to find your due date. This is more accurate than LMP for women with irregular cycles.
• IVF Transfer: For IVF pregnancies, the due date is extremely precise. It is calculated based on the transfer date and whether it was a Day 3 or Day 5 embryo transfer.
• Ultrasound: Early ultrasounds (dating scans) measure the baby's size to determine gestational age. You can enter the date of your scan and the weeks/days measurement to get an accurate EDD.

Is the Due Date Exact?

It is important to remember that a "due date" is just an estimate. Only about 4% of babies are born on their exact due date. Most healthy babies arrive within two weeks before or after this date (between 38 and 42 weeks).

Pregnancy Milestones

Use the timeline above to track key events like the end of the first trimester (lower miscarriage risk), the anatomy scan (gender reveal), and when your baby is considered full term.