Pregnancy Due Date Calculator — Estimated Date Calculator

Date & Time

Pregnancy Due Date Calculator is a date tool that estimates a due date from the last menstrual period from the last menstrual period and cycle information.

Important basis and limitations

Basis date
Content basis date: 2026-06-25
Scope
A general reference date calculation

This is a reference calculation from public sources and your inputs. It may not reflect personal circumstances, recent changes, or an authority’s interpretation. Confirm with an official source or qualified professional before filing, contracting, clinical care, contraception, or another important decision.

What is it

Pregnancy Due Date Calculator calculates a reference estimate in your browser. Actual dates can vary by cycle pattern, ultrasound findings, and clinical assessment, so this tool should not be used for medical decisions or contraception.

due date = first day of last period + 280 days + (average cycle - 28 days)

How to use

  1. 1Enter the first day of the last menstrual period.
  2. 2Enter average cycle length when needed.
  3. 3Press calculate to see the reference estimate.

Reference

Pregnancy Due Date Calculator — Estimated Date Calculator Reference
InputResult
2026-01-01estimates a due date from the last menstrual period

Sources & standards

FAQ

Is Pregnancy Due Date Calculator a diagnosis?

No. This tool provides a general date-based estimate and does not replace clinical care or medical judgment.

Is Pregnancy Due Date Calculator input sent to a server?

No. This tool runs in your browser and does not send input to a server.

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