Pregnancy Calculator
Calculate your estimated due date and track pregnancy milestones
weeks
days
How Due Date is Calculated
Naegele's Rule (LMP Method)
Add 280 days (40 weeks) to the first day of your last menstrual period.
Ultrasound Method
The due date is calculated from the ultrasound date by adding the remaining time from 40 weeks minus current gestational age.
Conception Date Method
Add 266 days (38 weeks) to the estimated date of conception.
Pregnancy Trimesters
| Trimester | Weeks |
|---|---|
| 1st Trimester | Week 1 – 13 |
| 2nd Trimester | Week 14 – 27 |
| 3rd Trimester | Week 28 – 40 |
About this Calculator
The Pregnancy Calculator is a free, easy-to-use tool for due date, conception, trimester. Simply enter your values and get instant, accurate results — no signup, no ads, no tracking. All calculations run locally in your browser, so your data stays completely private.
Privacy Note: All calculations are performed locally in your browser. No data is ever sent to a server or third party.