When will my baby be born?
Your baby’s estimated due date is 40 weeks after the first day of your last period. But babies do not read calendars: most arrive in the weeks around the due date, and a birth anywhere from 37 weeks to 42 weeks is considered to be within the normal range. The calculator shows both your estimated due date and that full birth window, so you can see the realistic span of dates when your baby might arrive.
Your baby’s birthday details
Many parents-to-be enjoy imagining their baby’s birthday. Based on the estimated due date, the result shows:
- Birth month and day of the week of the due date.
- Zodiac sign — if your due date is near the edge of a sign, your baby could just as easily be born under the neighbouring one.
- Birthstone for the due-date month, using the modern birthstone list (garnet for January through turquoise for December).
- Season of the due date (northern hemisphere).
Treat these as fun, not facts — a baby due on the 30th of the month could well have a birthday in the next month.
How likely is a birth on the due date?
Only a small minority of babies — often quoted at around 4–5% — are born on their exact due date. A large share arrive in the week before or after, and most are born within about two weeks of it. If you are planning visits, leave or travel around the birth, plan for the whole window rather than one day.
Your baby’s birth month: what to expect
Because the realistic birth window runs from 37 to 42 weeks, a due date near the start or end of a month gives a real chance of a birthday in the neighbouring month. A due date on the 3rd, for example, puts nearly three weeks of the window in the previous month. When you plan things like announcements, family visits or a nursery theme, it helps to keep both months in mind.
| Due date falls… | Birth month to plan for |
|---|---|
| in the first week of the month | Late in the previous month or early this month |
| mid-month | Most likely this month |
| in the last week of the month | Late this month or early next month |
Getting ready before the due date
- From about 34–36 weeks: prepare a hospital or birth bag and install the car seat if you will need one.
- By 37 weeks (early term): make sure you know how to contact your care team when labour starts and who will look after anything at home.
- Around the due date: keep your plans flexible — most babies arrive within about two weeks either side.
These are general planning ideas; your midwife or doctor will tell you what applies to your pregnancy.
Counting down to your baby
Use the Days Until Date calculator to count down to your due date, and the Pregnancy Timeline to see every week in between. The Pregnancy Due Date Calculator adds milestone dates such as full term and the anatomy-scan window.