🤰
Pregnancy Due Date Calculator
Estimate your baby's due date and track pregnancy milestones using Naegele's Rule.
🤰
Due Date Calculator
Naegele's Rule + cycle adjustment
days
How Due Date is Calculated
The most common method for calculating due date is Naegele's Rule, which adds 280 days (40 weeks) to the first day of your last menstrual period (LMP). This assumes a regular 28-day cycle. If your cycle differs, the calculator automatically adjusts.
Due Date = LMP + 280 days + (cycle length − 28 days)
Pregnancy Trimesters
| Trimester | Weeks |
|---|---|
| First Trimester | Weeks 1–13 |
| Second Trimester | Weeks 14–27 |
| Third Trimester | Weeks 28–40+ |