Pregnancy Due Date Calculator

A pregnancy due date calculator is a tool that estimates the date your baby is expected to be born based on the first day of your last menstrual period (LMP), conception date, IVF transfer date, or ultrasound gestational age. The most common method is Naegele's Rule: add 280 days (40 weeks) to the first day of your LMP. This assumes a 28-day cycle with ovulation on Day 14 — the pregnancy due date calculator adjusts for different cycle lengths automatically. The estimated due date is also called the EDD (Estimated Delivery Date) or EDC (Estimated Date of Confinement). Only about 5% of babies are born on their exact due date — normal delivery occurs between 37 and 42 weeks.

1. Choose Your Calculation Method: Select from LMP (most common), conception/ovulation date, IVF Day 3 embryo transfer, IVF Day 5 blastocyst transfer, or ultrasound gestational age. Each method uses a different formula to calculate the same estimated due date.
2. Enter Your Date:Input the relevant date and any additional parameters (cycle length for LMP, or gestational weeks/days for ultrasound). Click “Calculate Due Date” — the pregnancy due date calculator runs entirely in your browser with no data sent to any server.
3. Review Your Results: The pregnancy due date calculator displays your estimated due date, current gestational week and day, trimester, pregnancy progress bar, key milestone dates with calendar dates, and week-by-week development notes for your current stage.

• Estimated Due Date: The date your baby is expected to be born, calculated using the appropriate formula for your chosen method. Displayed with the full day of the week and date.
• Gestational Age: Your current pregnancy stage in weeks and days, counted from the first day of your LMP (not from conception). This is the standard used by healthcare providers worldwide.
• Trimester and Progress: Which trimester you are in (1st: weeks 1–13, 2nd: weeks 14–27, 3rd: weeks 28–40) and the percentage of your pregnancy completed, shown on a color-coded progress bar.
• Milestone Timeline: Key prenatal appointments and development milestones with their calendar dates — from the first prenatal visit to the anatomy scan, glucose screening, and full-term start date.

The pregnancy due date calculator provides an estimate — not a guaranteed delivery date. Due dates calculated from LMP assume a regular 28-day cycle with ovulation on Day 14; women with irregular cycles may have a different actual conception date. Ultrasound dating in the first trimester (before 14 weeks) is the most accurate method and may override the LMP-based due date if there is a significant discrepancy. The pregnancy due date calculator is a planning tool — always confirm your due date with your obstetrician or midwife, who will use clinical examination and ultrasound findings to establish your official EDD.