Free Pregnancy Due Date Calculator Online
Estimate your due date, current week, and pregnancy milestones
Complete Pregnancy Tracking
Due date, weekly progress, and milestone tracking in one tool
Calculate your estimated due date using the standard Naegele method adjusted for your personal cycle length.
See exactly which week of pregnancy you are in and what percentage of the journey is complete.
View important pregnancy milestones and trimester dates so you know what to expect and when.
About Our Pregnancy Calculator
Our free pregnancy calculator estimates your due date using the Naegele rule adjusted for your cycle length. It shows your current week, trimester, days remaining, and important milestones throughout your pregnancy journey.
Frequently Asked Questions
How is the due date calculated?
The calculator uses the Naegele rule, which adds 280 days (40 weeks) to the first day of your last menstrual period, adjusted for your cycle length if it differs from 28 days.
This is the same method used by most healthcare providers for initial due date estimation.
Only about 5% of babies are born on their exact due date, so consider this an estimate within a two-week window.
What if my cycle is not 28 days?
Enter your actual average cycle length and the calculator adjusts the due date accordingly. Longer cycles push the due date later and shorter cycles bring it earlier.
This adjustment accounts for the fact that ovulation occurs approximately 14 days before the end of your cycle, not necessarily on day 14.
If you are unsure of your cycle length, the default 28-day value provides a reasonable estimate.
What are the three trimesters?
The first trimester covers weeks 1 through 12 and includes early development and organ formation. The second trimester spans weeks 13 through 27 when the baby grows rapidly and movements become noticeable.
The third trimester runs from week 28 to delivery around week 40, during which the baby gains weight and prepares for birth.
Each trimester has distinct milestones and healthcare recommendations.
How accurate is this calculator?
The calculator provides an estimate based on standard obstetric methods. Actual due dates can vary based on individual factors including ovulation timing and fetal development.
An ultrasound dating scan in the first trimester typically provides the most accurate due date estimate.
Always consult your healthcare provider for personalized pregnancy care and accurate dating.