Standard is 28 days. Adjust if your cycle is regularly longer or shorter.
Estimated due date
Sunday, December 6, 2026
Estimated conceptionMar 15, 2026
End of 1st trimesterMay 31, 2026
End of 2nd trimesterSep 6, 2026
Key milestones
| 12 weeks | End of first trimester | May 24, 2026 |
| 20 weeks | Halfway / anatomy scan | Jul 19, 2026 |
| 24 weeks | Viability milestone | Aug 16, 2026 |
| 28 weeks | Third trimester begins | Sep 13, 2026 |
| 37 weeks | Full term begins | Nov 15, 2026 |
This is an estimate based on Naegele's rule. Only about 1 in 20 babies arrive on the exact due date. Your healthcare provider's dating, especially from an early ultrasound, is the most accurate.