Pregnancy Due Date Calculator

Estimate due date

Naegele's rule: LMP + 280 days (40 weeks). Other inputs supported: conception or ultrasound date.

Estimated due date (EDD)
Conception date
End of 1st trimester
End of 2nd trimester

Standard 40-week gestation from LMP. Day-5 IVF transfers add 261 days to transfer (40w − 19d). Adjust for non-28-day cycles.

About this tool

Pregnancy Due Date Calculator is a single-purpose utility on instant.tw, a free toolbox of calculators, converters, generators, and quick lookups. Everything works in your browser — nothing is uploaded, nothing is stored on a server unless explicitly noted.

Category: Women's Health — Pregnancy. Browse more Women's Health — Pregnancy tools.