Track your pregnancy weeks and days instantly today. Compare methods from dates and scans easily. Export results, plan milestones, and share with clinicians securely.
| Scenario | Input | Typical output |
|---|---|---|
| Last period method | LMP: 2026-01-01, Cycle: 28 | Weeks+days, trimester, due date |
| Due date method | Due: 2026-10-08, Cycle: 30 | Estimated LMP, weeks+days today |
| Ultrasound method | Scan: 2026-02-10, GA: 9w2d | Estimated LMP, due date, milestones |
Gestational age is counted from the first day of the last menstrual period, although conception occurs later. Many clinicians confirm dating with early ultrasound. This calculator accepts last period date, a clinic due date, an approximate conception date, or ultrasound dating. It returns weeks and days for today and generates milestone dates to support appointment planning.
A 28‑day cycle assumes ovulation near day 14. Longer or shorter cycles can shift estimates when only last period is known. The tool applies an adjustment equal to cycle length minus 28 days to the standard 280‑day timeline. For example, a 32‑day cycle adds four days. Once ultrasound dating is available, follow your clinician’s estimate.
Dates are converted to whole days, then divided by seven to report weeks plus remaining days. If today is 73 days after the last period date, the result is 10 weeks 3 days. Reporting both parts helps when screening windows are narrow. The summary also shows days remaining to the estimated due date to track progress toward term.
With an ultrasound date and the gestational age on that scan, the calculator back‑calculates an estimated last period date by subtracting scan age in days. That estimated last period date then drives today’s gestational age and due date. If you already have a clinic due date, compare outputs. Differences can occur with irregular cycles or uncertain last period timing.
The calculator lists typical milestone dates at 12, 20, 28, 37, and 40 weeks. These often align with early screening, the anatomy scan window, third‑trimester monitoring, early‑term readiness, and the estimated due date. Use milestones to schedule visits, prepare questions, and coordinate travel or leave planning around realistic timeframes.
The Plotly timeline shows progress from week 0 to week 40 and marks your current position. Use it to explain dates during appointments or to share a clear snapshot with family. CSV and PDF downloads create a compact record for your phone or printout, for quick reference. This tool is educational and should not replace medical guidance, especially with symptoms or complications.
Which date is best to use?
If you know the first day of your last period, start there. If an early ultrasound or clinician due date is available, prefer that dating for consistency across appointments.
What if my cycles are irregular?
Cycle adjustment is a simple estimate. With irregular cycles, ovulation timing varies, so early ultrasound dating is often more reliable than last-period calculations.
Does this calculate conception exactly?
No. The conception date shown is an approximation based on typical ovulation timing. Fertility windows differ, and sperm can survive several days.
Why do weeks and days matter?
Many tests and scans are scheduled within narrow week ranges. Seeing both weeks and days helps you understand whether you are inside a recommended window.
Can I download results for my doctor?
Yes. Use the CSV or PDF buttons to save a summary of dates and milestones. Bring it to visits to discuss with your clinician.
What if the result seems wrong?
Recheck the selected method and date formats. If you have bleeding, pain, or other concerning symptoms, contact a healthcare professional promptly.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.