How does the Gestational Age Calculator work?

Naegele's rule: Add 7 days to LMP, then add 9 months Then: Or: LMP + 280 days ≈ EDC Then: Verify with first-trimester ultrasound for accuracy.

Can you give an example of how to use the Gestational Age Calculator?

Example: Input LMP January 1 gives a result of EDC ≈ October 8 (280 days later) (Average pregnancy duration).

Is the Gestational Age Calculator free to use?

Yes — completely free with no registration, download, or subscription required. All calculations happen instantly in your browser.

How accurate is the Gestational Age Calculator?

Our Gestational Age Calculator uses verified mathematical formulas and is accurate to multiple decimal places. Results are calculated in real-time using the same methods used by professionals.

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Gestational Age Calculator

Gestational Age from LMP

Last Menstrual Period (YYYY-MM-DD)

Gestational age is pregnancy duration from last menstrual period. It's critical for fetal development assessment and delivery timing.

Difficulty:beginner

References

›Gestational Age — Wikipedia

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Gestational Age Calculator

Gestational Age from LMP

What is Gestational Age Calculator?

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