What's the difference between EDD and due date?
Same concept—both estimate when baby will arrive based on LMP or ultrasound.
Health Fitness
Estimated Delivery Date Calculator
Calculate estimated delivery date with your details.
Personalized estimate
Use realistic inputs for the most useful results.
What this calculator does
Estimated delivery date predicts when baby will arrive, typically 40 weeks from LMP. Normal delivery range is 37-42 weeks.
How it works
Uses Naegele's rule: LMP + 280 days. Conception-based alternative: Conception + 266 days.
Formula
EDD = LMP + 280 days. Or: Conception Date + 266 days.
Tips for using this calculator
- Track cycle length for accurate LMP-based calculation
- Early ultrasound (8-12 weeks) provides best dating
- Prepare for 37-42 week delivery window
- Learn signs of labor onset
- Discuss birth plan with healthcare provider
Frequently asked questions
What if baby doesn't come by due date?
Post-term is after 42 weeks. Doctors typically discuss induction options between 41-42 weeks.
How does ultrasound change the date?
If ultrasound dating differs significantly from LMP calculation, doctors adjust based on ultrasound.