🤰

Pregnancy Due Date Calculator

Estimate your due date from your last menstrual period.

Estimating your due date

The most common method (Naegele's rule) adds 280 days — about 40 weeks — to the first day of your last menstrual period. This is an estimate; only about 5% of babies arrive on the exact date. Always confirm with your doctor.

Frequently Asked Questions

What is the Pregnancy Due Date Calculator?

Estimate your due date from your last menstrual period. It runs instantly in your browser and is completely free.

Is the Pregnancy Due Date Calculator free and does it require signup?

Yes. Every calculator on Calculatis is 100% free with no registration, and the values you enter are never stored.

How accurate is the Pregnancy Due Date Calculator?

It uses standard, widely-accepted formulas. Results are reliable estimates for general use and are not a substitute for professional advice.