EEasynivo
Free health planning tool

Pregnancy Due Date Calculator

Estimate a due date from the first day of the last menstrual period and usual cycle length.

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Result

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Enter values and select Calculate.

Method and assumptions

Adds 280 days to the first day of the last menstrual period, adjusted by the difference from a 28-day cycle.

Important limitations

An early ultrasound is more accurate for confirming gestational age. Ask a qualified clinician for pregnancy care.

Official references

Transparency

Sources & methodology

Calculation method
Adds 280 days to the first day of the last menstrual period, adjusted by the difference from a 28-day cycle.
Evidence basis
Published health guidance combined with a simplified planning estimate.
Applies to
No statutory reference year. Results use the values and assumptions entered now.
Last reviewed
Limitations
An early ultrasound is more accurate for confirming gestational age. Ask a qualified clinician for pregnancy care.

Sources

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Content basis and verification

· Calculations run in your browser. Check the formula and assumptions on this page, and confirm important financial, tax, medical or legal decisions against current official guidance.