Enter Pregnancy Details
Example Data Table
| Method | Primary Input | Current Date | Cycle | Sample Result |
|---|---|---|---|---|
| LMP Date | 2026-02-26 | 2026-04-09 | 28 days | 6 weeks 0 days, due 2026-12-03 |
| Conception Date | 2026-03-01 | 2026-04-09 | 28 days | 7 weeks 4 days, due 2026-11-22 |
| Due Date | 2026-11-12 | 2026-04-09 | 28 days | 9 weeks 0 days, LMP 2026-02-05 |
Formula Used
LMP method: Gestational Age = Current Date − LMP Date.
Due Date from LMP: LMP Date + 252 days + Cycle Length.
Conception method: Gestational Age = (Current Date − Conception Date) + 14 days.
Due Date from Conception: Conception Date + 266 days.
Due-date method: Estimated LMP = Due Date − (252 days + Cycle Length).
Ultrasound method: Estimated LMP = Ultrasound Date − Measured Gestational Days.
Trimester guide: First through 13 weeks 6 days, second through 27 weeks 6 days, then third trimester.
How to Use This Calculator
1. Select the dating method that matches your available information.
2. Enter the current date. The form uses today by default.
3. Add cycle length if you know it. A 28-day cycle is standard.
4. Fill only the fields linked to your chosen method.
5. Press the calculate button to see the result above the form.
6. Review gestational age, trimester, due date, milestones, and remaining weeks.
7. Export the result as CSV or PDF for planning or record keeping.
Current Gestation Guide
Why current gestation matters
Current gestation tells you how far a pregnancy has progressed today. It is measured in weeks and days. This number guides prenatal care. It also helps families understand what stage comes next. Many appointments, scans, and tests depend on accurate timing.
Common ways to date pregnancy
The most common method uses the first day of the last menstrual period. This is called LMP dating. Some people know the conception date instead. Others may only know the estimated due date. Early ultrasound can also improve dating when cycle history is uncertain.
Why weeks and days both matter
Pregnancy is not tracked in months alone. Weeks and days are more precise. A result like 18 weeks 3 days gives better context than saying four months. That extra detail helps when reading scan reports, planning checkups, and following fetal growth milestones.
What the calculator shows
This calculator estimates current gestational age, trimester, estimated due date, and remaining time to forty weeks. It also shows milestone dates. These include twelve weeks, twenty weeks, viability planning points, and the term window. That makes the result useful for both planning and education.
How cycle length affects dating
Cycle length can shift the expected due date. A longer cycle may push ovulation later. A shorter cycle may move it earlier. That is why this tool lets you adjust cycle length. It can improve estimates when LMP is known but ovulation timing varies.
How ultrasound dating helps
Ultrasound dating is often helpful in early pregnancy. It estimates gestational age from measured fetal development. That is useful when periods are irregular or dates are unclear. It can support better planning for scans, screening, and routine prenatal visits.
Use results carefully
This tool is designed for general information. It supports tracking and planning. It does not diagnose problems. It does not replace professional care. If your dates conflict, symptoms change, or your care team gives different timing, follow clinical guidance.
FAQs
1. What is current gestation?
Current gestation is the present pregnancy age measured in weeks and days. It usually starts from the first day of the last menstrual period, not from conception.
2. Which input method is best?
LMP is common when periods are regular. Early ultrasound can be very useful when cycle timing is uncertain. Use the method that best matches reliable information.
3. Why does gestational age differ from fetal age?
Gestational age starts about two weeks before conception in standard obstetric dating. Fetal age starts near conception, so it is usually about fourteen days less.
4. Can cycle length change the due date?
Yes. A longer or shorter cycle can shift ovulation timing. That can move the estimated due date when calculation starts from LMP.
5. Is the due date exact?
No. It is an estimate. Birth can happen before or after that day. The date helps planning, but it is not a guarantee.
6. When does the third trimester start?
The third trimester begins after 27 weeks and 6 days. In practical use, many people say it starts at week 28.
7. Can I use this tool after an ultrasound?
Yes. Enter the ultrasound date and the measured gestational weeks and days. The calculator will estimate LMP, due date, and current gestation.
8. Should this replace prenatal advice?
No. Use it for education and planning only. Always rely on your clinician for medical decisions, date confirmation, and pregnancy care.