Due
Date
Calculator

Calculate your estimated due date, gestational age, trimester timeline, and pregnancy milestones from your last menstrual period.

Input

Estimated Due Date

Your baby is due

Mar 27, 2027

Gestational Age0 weeks, 0 days
Estimated ConceptionJul 4, 2026
Current Trimester1st Trimester

How It Works

This calculator uses Naegele's rule: add 280 days (40 weeks) to the first day of your last menstrual period (LMP) to estimate your due date.

If your cycle length differs from 28 days, the estimate adjusts accordingly. A longer cycle shifts the due date later; a shorter cycle shifts it earlier.

This calculator provides estimates only. Actual due dates may vary. Consult your healthcare provider for personalized guidance.

Trimester Breakdown

1st TrimesterWeeks 1–12
Jun 20, 2026 – Sep 18, 2026
2nd TrimesterWeeks 13–26
Sep 19, 2026 – Dec 25, 2026
3rd TrimesterWeeks 27–40
Dec 26, 2026 – Mar 27, 2027

Key Milestones

First Heartbeat Detectable~Week 6
Aug 1, 2026
End of First Trimester~Week 12
Sep 12, 2026
First Fetal Movement~Week 18
Oct 24, 2026
Viability Milestone~Week 24
Dec 5, 2026
Third Trimester Begins~Week 27
Dec 26, 2026
Full Term~Week 37
Mar 6, 2027

Learn more

How do cycle trackers predict ovulation, and why do cycle lengths vary?

Due Date Calculator | ToolsCanvas