HealthUpdated 2026-05-19

Pregnancy Due Date Calculator

Estimate a due date from a last-period date using an editable day offset.

Start dateDays to addMonths to add

Start using it Formula and examples

Enter assumptions

Start with the inputs that actually change the result.

OUT

Check the result

The live panel updates the main number and supporting outputs.

Open context only when needed

Formula notes, FAQ, and related guides stay below the tool.

Inputs

Pregnancy Date Calculator

Results update as you type.

Live result

Result date

2027-01-17

Total days changed

280

Scenario compare

Save scenario A, change a few inputs, then save scenario B.

Scenario A

Not saved yet

Scenario B

Not saved yet

Quick check

Change one or two inputs to compare a second scenario before using the number.

Need more detail?

Formula, examples, and FAQ stay tucked away until you need them.

FXFormula ExplanationThe core logic behind the numbers on this page.+

Our pregnancy due date calculator uses a straightforward approach to estimate your due date. We add calendar months first, then days, using a UTC date calculation to ensure accuracy. This method avoids time-zone drift and provides a reliable estimate.

USEHow to UseA short path from input to result.+

Enter the requested inputs.
Keep any editable rule or rate fields aligned with your situation.
Review the result and notes before using the estimate.

EXExamplesReference scenarios to sanity-check your inputs.+

Adjust the defaults to match your scenario, then calculate the estimate.

FAQFAQCommon edge cases and quick clarifications.+

What is the purpose of this calculator?

This calculator is designed to provide an estimate of your due date for planning purposes only. It's not intended for medical or legal decisions.

Can I adjust the assumptions?

Yes, you can edit the rate and rule fields to match your specific situation. This includes editable fields for varying rules by place, provider, or date.

What is the accuracy of this estimate?

This calculator provides an estimate based on a straightforward approach. However, please note that this is not a substitute for medical or official advice, and you should verify the estimate with a healthcare professional when making important decisions.

Is this calculator original?

Yes, our calculator uses an original implementation and rewrites the calculator structure, labels, formulas, and copy to provide a unique experience.

MAPRelated CalculatorsNeighboring tools in the same decision flow.+