Due Date Calculator Estimate Your Due Date

Your estimated due date is a wonderful guide, but it's not a strict deadline. Only about 5% of babies are born on their exact due date, so it's more of a general timeframe to help you and your care team prepare. A healthy full-term pregnancy can naturally range from 37 to 42 weeks, so your baby might arrive a little earlier or later.

Not remembering your LMP is totally common, and we can still help you estimate your due date. If you know your conception date, that's a fantastic starting point. Otherwise, your healthcare provider can use an early ultrasound to get a more accurate estimate of your baby's gestational age, which is often the most precise method.

Yes, sometimes your due date might be adjusted, especially after an early ultrasound. This scan provides a very precise measurement of your baby, which can refine the initial estimate based on your LMP. It's usually a small adjustment, but it helps ensure you're getting the most accurate information for your journey.

The most common way to calculate a due date is using Naegele's Rule. This method adds 280 days (or 40 weeks) to the first day of your last menstrual period. It assumes a 28-day cycle with ovulation on day 14, giving you a general timeline to help you understand your pregnancy progress.

Gestational age is counted from the first day of your last menstrual period, making it about 40 weeks for a full-term pregnancy. Fetal age, on the other hand, is counted from the date of conception, which is typically two weeks after your LMP. Most healthcare providers refer to gestational age, as it's easier to pinpoint the LMP and track development.

If you conceived through IVF, your due date calculation is often very precise. Instead of relying on your LMP, it's based on the date of your egg retrieval or the date of embryo transfer, adjusted by the age of the embryo. This usually provides a highly accurate starting point for your pregnancy timeline, offering extra peace of mind.

Once you have an estimated due date, you might start noticing various early pregnancy signs like fatigue, nausea, or breast tenderness. Every body is different, so some women experience many symptoms, while others have very few. You can learn more about what to expect and how to navigate these changes in our article on early pregnancy signs.

While a due date calculation can give you a rough idea, it's best to take a pregnancy test around the time of your missed period for the most accurate results. Home pregnancy tests work by detecting hCG, a hormone that increases rapidly in early pregnancy. If you get a positive result, our guide on positive pregnancy test next steps can be a helpful companion.