Enter tracking details
This page uses a stacked page layout, while the input form switches to three columns on large screens, two on medium screens, and one on mobile.
Example data table
| Example | Dating Method | Input Values | Sample Output |
|---|---|---|---|
| Example A | LMP | LMP: Jan 15, 2026 Cycle length: 28 days As of: Mar 23, 2026 |
Week 10 Gestational age: 9 weeks, 4 days EDD: Oct 22, 2026 |
| Example B | Due date | EDD: Nov 12, 2026 As of: May 21, 2026 |
Week 16 Second trimester Roadmap and milestone windows shown |
| Example C | IVF transfer | Transfer: Feb 10, 2026 Embryo age: 5 days As of: Apr 7, 2026 |
Gestational age estimated from transfer-adjusted dating EDD and visit windows recalculated |
Formula used
1) LMP-based due date
Estimated Due Date = LMP + 280 days + (Cycle Length − 28 days)
2) Due-date method
LMP = Due Date − 280 days, then gestational age is measured from that LMP.
3) Conception-date method
Estimated Due Date = Conception Date + 266 days
4) IVF transfer method
Estimated Due Date = Transfer Date + (266 − Embryo Age in Days)
5) Gestational age
Gestational Age in Days = As Of Date − LMP Date
6) Tracking week and completion
Tracking Week = floor(Gestational Age in Days ÷ 7) + 1
Progress % = (Gestational Age in Days ÷ 280) × 100
How to use this calculator
- Choose the dating method that matches the information you already know.
- Enter the required date fields, plus cycle length when you use the LMP method.
- Select the date you want to track against, usually today.
- Press Track Pregnancy Week to show the result above the form.
- Review your week number, gestational age, trimester, milestone windows, and roadmap table.
- Use the CSV or PDF buttons to download a summary for records or appointments.
FAQs
1) Which method is best for most people?
The LMP method is the most common starting point when periods are reasonably regular. If dates are uncertain, scan-based dating or a clinician’s estimate may be more accurate.
2) Why can the due date change?
Due dates are estimates, not guarantees. Irregular cycles, uncertain ovulation timing, IVF timing, and early ultrasound findings can all shift the expected date.
3) Does week counting start at conception?
Usually no. Standard pregnancy dating starts from the first day of the last menstrual period, which is about two weeks before conception in a typical cycle.
4) Are the weekly size comparisons exact?
No. They are simple visual comparisons meant to make progress easier to understand. Actual fetal size varies and medical scans provide the most precise measurements.
5) Can I use this after IVF?
Yes. The IVF option adjusts the due date by transfer date and embryo age, which is a common way to estimate pregnancy timing after assisted reproduction.
6) Why are milestone windows shown as ranges?
Many screenings and scans happen within recommended windows rather than on one exact day. Providers schedule within those ranges based on access, risk, and clinical preference.
7) What if my result looks different from my clinic date?
Use your clinician’s dating if it differs from a simple calculator. Ultrasound findings, IVF data, or cycle variation may create a more accurate official pregnancy timeline.
8) Is this calculator a medical decision tool?
No. It is a planning and tracking aid. Symptoms such as bleeding, severe pain, reduced movement, fever, or urgent concerns should be discussed with a medical professional promptly.