Pregnancy Due Date Calculator
Estimates the due date from the last menstrual period (Naegele's rule with cycle length adjustment), a known conception date, or an IVF transfer day, plus gestational age today and a table of milestone dates.
Read the full guide to this tool
Results
Notes
- Naegele's rule: due date = LMP + 280 days, adjusted by (cycle − 28) for longer or shorter cycles.
- Only about 4–5 % of babies arrive on the due date itself; most arrive within two weeks either side. A first-trimester ultrasound gives the most reliable dating.
- This is an educational estimate, not medical advice; consult a professional for decisions about your health.
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