This free pregnancy conception calculator estimates a range of conception dates based on a provided due date, last period date, or ultrasound date.

This conception calculator will help you estimate the conception date of your child.

Our conception calculator, also known as a reverse due date calculator, is the answer to the question "When did I conceive?" as it estimates when your pregnancy was conceived.

Aug 5, 2025 · Enter LMP, due date, or ultrasound to find your conception date and likely window - plus a clean timeline of key pregnancy dates.

Dec 4, 2025 · Advanced pregnancy due date calculator — LMP, Ultrasound, Reverse Ultrasound (EDD known), or IVF/ART. Produces EDD, Gestational Age today, calculated LMP, and estimated …

Jun 6, 2025 · Our Conception Date Calculator uses your due date to estimate when you got pregnant. (If you don't know your due date yet, just head over to our Due Date Calculator.)

Sep 26, 2024 · Use our Conception Date Calculator to find out the most likely date you conceived your little bundle. You may even be able to use your conception date to see how far along you are and …

Dec 1, 2025 · Estimate your conception date, fertile window, and pregnancy trimesters instantly with our easy-to-use Baby Conception Calculator tool.

Calculate a conception date based on your due date, a DOB or your last menstrual period.

A conception calculator calculates your possible conception date by counting back from your estimated due date (EDD) or counting forward from your last menstrual period (LMP).