Pregnancy Due Date Calculator
Your Pregnancy Details
What is a Pregnancy Due Date Calculator?
A Pregnancy Due Date Calculator is an online tool that predicts your baby’s expected birth date based on:
✅ First day of last menstrual period (LMP)
✅ Average cycle length
✅ Estimated conception date
Healthcare providers use similar calculations (like Naegele’s Rule) to determine your 40-week pregnancy timeline.
How to Use Our Pregnancy Due Date Calculator
Simple Steps to Calculate Your Due Date:
- Enter the first day of your last period
- Select your average cycle length (default is 28 days)
- Click “Calculate Due Date”
- Get instant results, including:
- Estimated due date
- Current pregnancy week & day
- Conception date
- Trimester timeline
- Pregnancy progress percentage
How Does a Due Date Calculator Work?
Most calculators use Naegele’s Rule:
Due Date = First day of LMP + 280 days
However, our advanced tool adjusts for your unique cycle length (21-35 days) for better accuracy.
Key Calculations:
| Metric | How It’s Calculated |
|---|---|
| Due Date | LMP + 280 days (adjusted for cycle length) |
| Conception Date | LMP + (Cycle Length – 14 days) |
| Current Week | Days since LMP ÷ 7 |
| Trimester | 1-13 weeks (1st), 14-27 weeks (2nd), 28-40 weeks (3rd) |
Why Is Knowing Your Due Date Important?
- Prenatal Care – Doctors schedule tests based on gestational age.
- Maternity Leave – Plan work leave around your due date.
- Baby Preparation – Nursery setup, buying essentials, etc.
- Mental Preparation – Track pregnancy milestones week-by-week.
How Accurate Are Due Date Calculators?
- Ultrasound dating (especially in the 1st trimester) is most accurate.
- Only 5% of women deliver on their exact due date – most deliver within 2 weeks before or after.
- Factors like irregular periods or IVF pregnancies may affect accuracy.
Due Date Estimation Chart
| Calculation Method | Accuracy |
|---|---|
| Last Menstrual Period (LMP) | ± 2 weeks |
| First-Trimester Ultrasound | ± 3-5 days |
| Conception Date | ± 1 week |
Pregnancy Week-by-Week Timeline
Our calculator also shows:
- Current pregnancy week (e.g., “Week 12, Day 5”)
- Trimester breakdown (1st, 2nd, 3rd)
- Progress bar (0% to 100%)
When to Expect Key Milestones:
- First Trimester (Weeks 1-13): Morning sickness, baby’s heartbeat detectable
- Second Trimester (Weeks 14-27): Baby kicks, gender reveal possible
- Third Trimester (Weeks 28-40): Final growth spurts, labor prep
FAQs About Pregnancy Due Date Calculators
Q1: Can I use this calculator if I have irregular periods?
Yes, but results may be less accurate. An early ultrasound provides better estimates.
Q2: Does the calculator work for IVF pregnancies?
For IVF, use the embryo transfer date instead of LMP for better accuracy.
Q3: Why is my due date different from my doctor’s estimate?
Doctors may adjust based on ultrasound measurements or other factors.
Q4: What if I don’t remember my last period date?
Try estimating or consult a doctor for an ultrasound dating scan.
Final Thoughts
A Pregnancy Due Date Calculator helps you plan for your baby’s arrival while tracking your pregnancy journey. Bookmark this tool to monitor your progress!
📌 Try it now and share with expecting parents!