Due Date Calculator Tool
Calculate your pregnancy due date using multiple methods
Due Date Calculator
Most common method
If you know conception date
For assisted reproduction
Based on ultrasound measurements
days
Due Date Results
Enter your information to calculate due date
Important Information
- Only 4% of babies are born on their exact due date
- Most births occur between 37-42 weeks of pregnancy
- Due dates are estimates - your baby will come when ready
- Always consult with your healthcare provider for accurate dating
- Methods may give slightly different results based on input data
Due Date Calculator
Calculate your expected due date using 4 different methods.
Calculation Methods
1. Last Menstrual Period (LMP)
Most common method: LMP + 280 days
2. Conception Date
Conception date + 266 days
3. IVF/IUI Dates
Special calculation for assisted reproduction
4. Ultrasound Dating
Most accurate, especially early ultrasound
Pregnancy Timeline
First Trimester
Weeks 1-12
Second Trimester
Weeks 13-26
Third Trimester
Weeks 27-40+
Important: Only 4% of babies are born on their exact due date. Most births occur between 37-42 weeks. This calculator provides estimates – always follow your healthcare provider's dating.
Frequently Asked Questions
Due date = First day of last period + 280 days (40 weeks). This is called Naegele's Rule.
Adjust: Due date = LMP + 280 days + (cycle length - 28 days). Our calculator accounts for cycle length.
Only 4-5% of babies are born on their due date. Most births occur between 37-42 weeks.
First trimester ultrasound (8-12 weeks) is most accurate, within 3-5 days.
Yes, early ultrasound may adjust due date, especially if LMP date is uncertain or cycles are irregular.
