Instant calculator
Due Date Calculator
This due date calculator uses the first day of the last menstrual period to estimate due date, conception date, and current pregnancy week.
How to use
Quick steps
- Enter first day of last period.
- Review the instant answer block and supporting calculations.
- Compare the result with related tools in the same category before making a decision.
Formula
How this calculator works
Estimated due date = LMP + 280 days
Due dates are estimates. A doctor or midwife can give a more precise timeline based on ultrasounds and cycle history.
FAQ
Common questions
How does the due date calculator work?
It uses Estimated due date = LMP + 280 days. Enter first day of last period to generate an instant estimate.
When should I use this due date calculator?
Estimate a pregnancy due date from the first day of the last menstrual period.
What should I keep in mind?
Due dates are estimates. A doctor or midwife can give a more precise timeline based on ultrasounds and cycle history.