Calculator inputs
Estimate a due date from the first day of the last menstrual period.
Enter the first day of the last period used for this estimate.
Formula
A last menstrual period starting on 2026-01-10 gives an estimated due date of 2026-10-17.
How to use it
Estimate a due date from the first day of the last menstrual period. This page keeps the steps simple, shows the core formula, and links to closely related tools so users can keep comparing scenarios.
Due Date Calculator FAQ
What does this calculator estimate?
Estimate a due date from the first day of the last menstrual period.
How should I read the result?
The result is a quick planning estimate based on the formula shown above.
Where should I go next?
Use the related links to compare adjacent calculators or open the category hub.
Accuracy and use of results
CalculatorWorks aims to make calculations clear and practical. We use standard calculation methods where possible, explain assumptions in plain language, and encourage users to verify important results before relying on them.