Clear estimate
See an estimated pregnancy week and due date in one place.
Pregnancy calculation and tracking
Plan your pregnancy week with a clear pregnancy calculator app
Pregnancy Tracking and Calculator uses the first day of your last menstrual period to provide an initial estimate of your pregnancy week and due date, then helps you organize week-by-week updates, baby development information, and personal records.
Pregnancy calculator app
Clear estimate
See an estimated pregnancy week and due date in one place.
Weekly context
Read clearly sourced information relevant to the estimated week.
One tracking space
Keep weight, blood pressure, glucose, and personal notes together.
Weekly context
Read clearly sourced information relevant to the estimated week.
One tracking space
Keep weight, blood pressure, glucose, and personal notes together.
Source transparency
Supported by official medical sources
You can open and review every reference on this page.
How does pregnancy week calculation work?
A common starting method counts approximately 40 weeks from the first day of the last menstrual period. The app uses that date to estimate the current pregnancy week and due date.
The result is an estimate. Cycle length, ovulation timing, and early ultrasound findings can change clinical dating. Your obstetric professional's assessment remains the basis for clinical decisions and prenatal care.
What does the pregnancy tracker add after calculation?
The app turns the estimated week into an organized tracking flow with week-by-week pregnancy content, general baby development information, appointment reminders, and dated measurement records.
- Week-specific content grounded in current medical sources
- Dated spaces for weight, blood pressure, and glucose records
- A way to review fetal movement and contraction entries over time
How should you use the estimate?
Use it as a practical reference for personal planning and discussions with your care team. An estimated due date is not a guaranteed delivery date, and the app does not diagnose conditions. Ask your clinician about uncertain dates or health concerns.
Medical information boundary
This page and the in-app calculation are for general information and personal tracking. They do not replace diagnosis, examination, or advice from your healthcare professional.
Common questions
Frequently asked questions
Does a pregnancy calculator app give an exact due date?
No. A last-menstrual-period calculation gives an estimate. Early ultrasound findings and clinical assessment may lead your care professional to use a different date.
Can I calculate my pregnancy week without knowing my last period?
The standard calculation may not be appropriate without that date. A healthcare professional can assess pregnancy dating using the information available to them.
Why is pregnancy dated from the last menstrual period?
Clinical pregnancy age is commonly counted from the first day of the last menstrual period because the exact day of fertilization is often unknown.
Source transparency
Medical references
This content refers to current guidance from the following official health organizations and relevant specialist content.
Complete your tracking
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Estimate your week and start tracking in one place
Download Pregnancy Tracking and Calculator free for iPhone or Android.