About This Calculator

Our Pregnancy Due Date Calculator helps expecting parents estimate their baby's due date and track key pregnancy milestones. It also generates a personalized "My Pregnancy Story" card that maps your journey to real-world events like holidays and seasons.

How It Works

Last Menstrual Period (LMP): Uses Naegele's Rule — adding 280 days (40 weeks) to the first day of your last period. If your cycle isn't 28 days, we adjust accordingly.

Conception Date: Adds 266 days (38 weeks) from your estimated conception date to calculate the due date.

IVF Transfer Date: For Day 3 embryo transfers, adds 263 days. For Day 5 (blastocyst) transfers, adds 261 days.

Known Due Date: If you already have a due date from your healthcare provider, we use it to generate your pregnancy timeline and story card.

Important Notes

Only about 5% of babies arrive on their exact due date. Your baby may come 2 weeks before or after.
Your healthcare provider may adjust your due date based on ultrasound measurements.
All calculations assume a standard pregnancy length. Individual variation is normal and expected.
This tool is for informational purposes only and does not constitute medical advice.

Medical Disclaimer

This calculator provides estimates based on standard medical formulas, including Naegele's Rule. The results are approximations and should not be considered a substitute for professional medical advice, diagnosis, or treatment.

Every pregnancy is unique. Due dates are estimates — only about 5% of babies are born on their exact due date. Your healthcare provider may adjust your due date based on ultrasound measurements and other clinical factors.

Always consult with your obstetrician, midwife, or healthcare provider for personalized medical guidance throughout your pregnancy.

References

American College of Obstetricians and Gynecologists (ACOG) — Methods for Estimating the Due Date
Naegele's Rule — Standard obstetric method for EDD calculation
Mayo Clinic — Fetal development week by week