Pregnancy Due Date Calculator

Estimate an expected due date by adding 280 days to the first day of the last menstrual period. It is educational only; cycle timing and clinical dating can change the estimate. Calculate it clearly with Figur.

How the pregnancy due date calculator works

Estimate an expected due date by adding 280 days to the first day of the last menstrual period. It is educational only; cycle timing and clinical dating can change the estimate.

Method and assumptions

Figur applies straightforward arithmetic to the values you enter. The calculation runs locally in your browser and is not stored.

  • The result depends on accurate inputs and units.
  • External factors, fees, taxes, or rules not requested by the calculator are not included.
  • Use the result as a planning estimate and verify any high-stakes decision.

Sources and references

No external data source is required: this calculator uses standard arithmetic and the values you enter.

Worked example

The first day of the last menstrual period was 2025-01-01.

The estimated due date is October 8, 2025.

Frequently asked questions

Is the due date exact?

No. It is an estimate; only a small share of births happen on the exact date.

What if my cycles are irregular?

This method may be less accurate. A prenatal clinician can date a pregnancy using your history and ultrasound when appropriate.

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