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Module · Pregnancy · Naegele's Rule
Due Date Calculator
Estimate your baby's due date (EDD) from your last menstrual period or conception date. Uses Naegele's rule with a cycle-length adjustment.
Calculate from
Estimates use Naegele's rule (LMP + 280d) or 266 days from conception. Not a substitute for an ultrasound scan.
Your dates
Estimated due date
Sun, February 14, 2027
Days remaining
217
Gestational age today
9w 0d
Trimester 1
1st (0–13w)
2nd (13–26w)
3rd (26–40w)
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Guide
How Due Date Calculator works
Step 01
Choose source
From LMP (first day of last period) — most common — or from conception date if you know it.
Step 02
Enter cycle length
Default 28 days. Longer cycles push EDD later; shorter cycles pull it earlier.
Step 03
See your EDD
Estimated due date + how many days remaining + gestational age today.
FAQ
Frequently asked
How accurate is the EDD?+
Only ~5% of babies arrive on their exact EDD. First-trimester ultrasound is the most accurate dating method.
LMP vs conception date — which is more accurate?+
LMP is easier to remember; conception date is more accurate if you know it (from ovulation tracking or IVF).
Can this be used for IVF pregnancies?+
Yes — use the conception mode and enter the date of egg retrieval + fertilisation.