About the Due Date Calculator
Estimated due date from your last menstrual period or conception date, using Naegele’s rule.
Also known as: pregnancy due date, edd calculator, when is my baby due, estimated delivery date, pregnancy countdown.
How to use this calculator
- Enter calculate from, date.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
Naegele's rule: due date = LMP + 280 days (adjusted for cycle length)
Worked example
Using the values pre-filled in the calculator above:
- Calculate from: Last menstrual period
- Date: 2026-07-24
- Average cycle length = 28 days
the calculator returns:
- Estimated due date: Friday, April 30, 2027
- Current gestational age: 8 weeks 4 days
- Days to go: 220
- Estimated conception: Friday, August 7, 2026