Pregnancy Due Date Calculator
Estimate your due date based on your last menstrual period or conception date. See your current pregnancy week, trimester, and key milestones — fast and free.
Due Date Calculator
Get Your Results Emailed
Enter your email and we'll send you a summary of your pregnancy due date calculator calculation. No spam, unsubscribe anytime.
About the Pregnancy Due Date Calculator
A due date calculator estimates when your baby will arrive using the standard Naegele rule, named after German obstetrician Franz Naegele. While only about 4% of babies arrive on their exact due date, knowing the estimated date helps you track pregnancy milestones and plan for your baby's arrival.
Quick Start Guide
- Enter your values — Fill in the fields with numbers relevant to your pregnancy due date calculation. Most fields include sensible defaults.
- Adjust settings — Change options like units, rates, or timeframes to match your specific scenario.
- Review results — The output shows a clear breakdown so you understand how the total was calculated.
How It Works
Naegele's rule: add 280 days (40 weeks) to the first day of your last menstrual period (LMP). This assumes a 28-day cycle with ovulation on day 14. For irregular cycles, the calculator adjusts based on your average cycle length.
Real-World Example
Scenario: LMP was January 15, 2026, with a 28-day cycle
- LMP date: January 15, 2026.
- Add 280 days: 40 weeks from LMP.
- Calculate: January 15 + 280 days.
Who Is This For?
This pregnancy due date calculator is designed for Health-conscious individuals tracking fitness goals, understanding body composition, and making informed wellness decisions.. It's intentionally simple — no complex signup forms, no data tracking, no distractions. Just enter your numbers and get the answer.
Pro Tip
Track your measurements over time rather than obsessing over single readings — trends are more meaningful than individual data points.
Things to Know
The pregnancy due date calculator provides instant, accurate results based on standard formulas and the values you enter. Whether you are planning a financial decision, tracking a health metric, or solving a practical problem, this tool gives you the numbers you need without requiring signup or account creation.
How to get the best results: Use accurate, up-to-date inputs for the most reliable calculations. When planning ahead, run multiple scenarios with different assumptions to understand the range of possible outcomes.
Note: This tool is designed for educational and planning purposes. For critical financial, medical, or legal decisions, always verify the results with a qualified professional who can evaluate your specific circumstances.
Sources & References
Explore More Health & Wellness
These related tools work well alongside the pregnancy due date calculator:
Frequently Asked Questions
How accurate is the due date?
Only about 4% of babies are born on their exact due date. Most (about 70%) are born within 10 days of their due date. A "full-term" pregnancy ranges from 39 weeks 0 days to 40 weeks 6 days. Babies born before 37 weeks are considered preterm.
Should I use this instead of seeing a doctor?
No. This tool provides educational estimates only. Always consult a healthcare professional for medical advice, diagnosis, or treatment.
How often should I use this tool?
Use it as often as you like. Tracking your results weekly or monthly can help you spot trends and monitor progress over time.
How accurate are the results?
Results are based on standard formulas and the values you enter. They are accurate for educational and planning purposes.
Is this tool really free?
Yes, completely free. No signup, no hidden charges, no usage limits. Use it as often as you need.
How to Use
Select whether to calculate based on your LMP or conception date. If using LMP, enter the first day of your last period and your average cycle length. The calculator uses Naegele's rule: 280 days from LMP, adjusted for cycle length.