👶 Pregnancy Due Date Calculator
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Estimate Your Baby’s Due Date With Confidence
This calculator uses the standard Naegele’s Rule to estimate your baby’s arrival date based on the first day of your last menstrual period (LMP). It also shows your current pregnancy week so you always know where you are in your journey.
What This Calculator Shows
- Estimated Due Date: Based on a typical 280‑day pregnancy.
- Current Pregnancy Week: Updated instantly from your LMP.
- Trimester Breakdown: Understand which stage you’re in.
How Naegele’s Rule Works
The formula adds 280 days (40 weeks) to the first day of your last menstrual period. While this is the standard method used worldwide, every pregnancy is unique — babies often arrive a little earlier or later.
What Affects Due Date Accuracy
- Irregular menstrual cycles
- Late ovulation
- IVF or assisted conception
- Ultrasound measurements (which may adjust the date)
Why This Tool Is Helpful
Knowing your estimated due date helps with planning prenatal appointments, tracking fetal development, and preparing for each trimester. It also gives you a clearer picture of your pregnancy timeline without needing to calculate manually.
Important Notes
Due dates are estimates — only about 5% of babies arrive exactly on their predicted date. Think of it as a helpful guide, not a precise countdown.
Disclaimer: This calculator is for informational purposes only and does not replace medical advice. Always consult your doctor or midwife for personalized guidance.
How Your Due Date Is Calculated
This tool uses Naegele’s Rule — the standard method used by doctors and midwives. Your estimated due date is 280 days (40 weeks) from the first day of your last menstrual period. It also calculates your current week of pregnancy and trimester.
Understanding Your Results
- Estimated Due Date: Only about 4% of babies are born exactly on their due date. It’s a target, not a deadline.
- Current Week: Pregnancy is measured in completed weeks. If you’re 20 weeks and 3 days, you’re in your 21st week.
- Trimesters: First (weeks 1-12), Second (weeks 13-26), Third (weeks 27-40).
Always confirm with your healthcare provider. This calculator gives you a quick estimate, but your doctor or midwife may adjust your due date based on ultrasound measurements and other factors.
Disclaimer: This is an educational estimate, not medical advice.