Are you curious about when you conceived?

Whether you’re tracking ovulation, planning future pregnancies, or just satisfying your curiosity, this free and accurate reverse due date calculator is here to help.

It’s based on standard pregnancy dating methods and gives you an estimate of your conception date in seconds.

Simply enter your due date below, and you’ll instantly discover your conception date.

What Is a Reverse Due Date Calculator?

Well, it’s like the opposite of a regular due date calculator.

Instead of predicting your baby’s due date based on your last menstrual period, it helps you figure out when conception likely occurred, based on your estimated due date.

If you’re unsure about your due date, visit my due date calculator.

Why Use a Reverse Conception Calculator?

Maybe you’re dreaming of a September baby and want to plan accordingly.

Or perhaps you’re curious about the timing of your own conception!

Whatever the reason, my calculator is here to assist you in a snap!

What Is the Date of Conception?

It’s the magical moment when sperm meets egg and the journey of new life begins!

But here’s the thing – figuring out the exact day of conception is a bit tricky.

Ovulation, the release of the egg, typically happens between days 11-21 of a woman’s monthly cycle. That’s quite a wide window, isn’t it?

To add to the mystery, conception can occur within hours or up to a week after intercourse!

How? Well, sperm can hang out inside a woman’s body for up to a week, patiently waiting for the egg to make its grand entrance.

Want to learn more about how conception really works and how to boost your chances of getting pregnant?
Check out my full guide here: How to Get Pregnant by Understanding Your Ovulation Cycle

How Is the Date of Conception Calculated?

It’s simple math!

For a standard 28-day cycle, subtract 266 days from your estimated due date, and voila – you’ve got your estimated date of conception.

So if your doctor gave you a due date based on an early ultrasound or other method, this calculator will tell you when you most likely got pregnant.

How Accurate Is It?

This tool provides an estimate, not an exact answer.

Several factors can affect when you actually conceived:

• Irregular menstrual cycles
  If your cycles aren’t regular, it’s harder to know exactly when you ovulated.
• Fertility treatments
  If you conceived through treatments like IUI or IVF, the timing may be controlled or different from natural conception.
• Late ovulation
  Some women ovulate later than expected, which can shift the actual conception date.

Ready to use the Due Date Reverse Calculator? Enter your due date to see when you likely conceived.