July 2026
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Pregnancy due date calculator
Estimate your due date using Naegele's rule (LMP + 280 days).
Estimate, not a diagnosis. This tool gives an educational estimate based on the numbers you enter. It cannot account for your individual health history — consult a healthcare professional for anything clinical.
How this is calculated
We apply Naegele's rule: add 280 days (40 weeks) to the first day of your last menstrual period, with a small adjustment if your average cycle differs from 28 days.
Outputs
- Estimated due date
- Current gestational age
Limitations
Ultrasound dating can be more accurate, especially if your LMP is uncertain. Use this estimate as a guide and confirm clinically.