Pregnancy Due Date Estimator

About This Pregnancy Calculator

This tool is designed to help expecting parents in the U.S. determine their estimated due date based on several medical starting points. You can calculate from your last menstrual period (LMP), conception date, ultrasound, known due date, or even an IVF transfer date.

How the Calculator Works

• LMP: Adds 280 days (40 weeks) to the first day of your last period.
• Conception: Adds 266 days from the conception date.
• Ultrasound: Based on fetal age, typically adds ~252 days.
• Due Date: Reverse-calculates gestational age if you already know your due date.
• IVF Transfer: Assumes embryo age and calculates ~266 days from transfer.

Trimester Breakdown

• First Trimester: Weeks 1–12 – critical development period.
• Second Trimester: Weeks 13–26 – growth & anatomy scans.
• Third Trimester: Weeks 27–40 – birth planning & frequent visits.

U.S.-Specific Pregnancy Tips

• Start prenatal care by 8 weeks of pregnancy.
• Take folic acid (400–800 mcg) daily to prevent birth defects.
• Schedule regular checkups and genetic screenings.
• Enroll in prenatal classes and childbirth education if available.
• Stay active and eat a balanced diet unless otherwise advised by your OB/GYN.

Disclaimer: This tool is for educational purposes only. Always consult your healthcare provider for personalized medical advice.