Pregnancy Calculator
Calculate your estimated due date, current pregnancy stage, and trimester from your last period.
Due Date (Naegele's Rule):
Due Date = LMP + 280 days (40 weeks)
Or: LMP + 9 months + 7 days
Current Gestational Age:
Weeks = (Today - LMP) / 7 days
Trimester Breakdown:
1st: Weeks 1-12 | 2nd: Weeks 13-27 | 3rd: Weeks 28-40
Due Date = LMP + 280 days (40 weeks)
Or: LMP + 9 months + 7 days
Current Gestational Age:
Weeks = (Today - LMP) / 7 days
Trimester Breakdown:
1st: Weeks 1-12 | 2nd: Weeks 13-27 | 3rd: Weeks 28-40
Example: Last period Jan 1, 2024 -> Due date Oct 8, 2024. At 20 weeks = halfway point (ultrasound anatomy scan week)
📐 Formula
Due Date (Naegele's Rule):
Due Date = LMP + 280 days (40 weeks)
Or: LMP + 9 months + 7 days
Current Gestational Age:
Weeks = (Today - LMP) / 7 days
Trimester Breakdown:
1st: Weeks 1-12 | 2nd: Weeks 13-27 | 3rd: Weeks 28-40
Due Date = LMP + 280 days (40 weeks)
Or: LMP + 9 months + 7 days
Current Gestational Age:
Weeks = (Today - LMP) / 7 days
Trimester Breakdown:
1st: Weeks 1-12 | 2nd: Weeks 13-27 | 3rd: Weeks 28-40
📝 Example Calculation
Example: Last period Jan 1, 2024 -> Due date Oct 8, 2024. At 20 weeks = halfway point (ultrasound anatomy scan week)