Pregnancy Due Date Calculator
Calculate based on the first day of your last menstrual period (LMP).
Pregnancy Information
Understanding Due Dates
A pregnancy due date is an estimate of when your baby will be born. Only about 4% of babies are actually born on their exact due date, with most births occurring within 2 weeks before or after.
Pregnancy Length
- Average pregnancy: 40 weeks (280 days) from the last menstrual period
- Full term range: 37-42 weeks
- From conception: Typically 38 weeks (266 days)
Pregnancy Trimesters
- First Trimester: Weeks 1-12
- Second Trimester: Weeks 13-26
- Third Trimester: Weeks 27-40
Important Notes
This calculator provides an estimate only. Your healthcare provider may adjust your due date based on additional information from ultrasounds and examinations.