Pregnancy Due Date Calculator
The pregnancy due date calculator estimates when your baby will arrive and tracks how far along you are, week by week. Enter one date and it returns your estimated due date (EDD), your conception estimate, and your current pregnancy progress in a single view.
Calculate from your last menstrual period (LMP), a known conception date, or a due date you already have from your doctor. The tool follows Naegele's rule — the standard 280-day method used by healthcare providers — and lets you fine-tune the result with your own cycle length. It is built for anyone who just found out they are expecting or wants a clearer picture of their pregnancy timeline.
How to Calculate Your Due Date
Choose a calculation method
Pick Last Period (LMP) if you know when your last period started (the most common method), Conception Date if you know when you conceived, or Known Due Date if your provider already gave you one.
Enter your date
Click the date field and choose the date from the calendar, or tap Today to set it instantly. Results update the moment a date is selected.
Adjust cycle length (LMP only)
If your menstrual cycle differs from the standard 28 days, use the plus and minus buttons to set it anywhere from 20 to 45 days. This shifts the estimated ovulation date and refines your due date.
Read your results
See your estimated due date with weekday, the approximate conception date, days remaining (or days past due), your current week and day on a progress bar, and a timeline of key milestones.
Copy your results
Tap Copy Result to put a summary — due date, conception date, current progress, and days remaining — on your clipboard for sharing or saving to your notes.
Features
Three Calculation Methods
Calculate your due date from your last menstrual period, a known conception date, or a due date already set by your provider.
Adjustable Cycle Length
In LMP mode, set your cycle anywhere from 20 to 45 days so the ovulation and due-date estimates fit your body, not just the 28-day average.
Visual Progress Tracking
A progress bar shows your current week and day, your trimester, and the percentage completed toward your due date.
Key Pregnancy Milestones
Track 10 milestones from week 4 to week 40 — each dated and marked as passed, current, or upcoming.
Days Remaining Counter
See exactly how many days are left until your due date — or how many days overdue you are once it passes.
Conception Date Estimate
Get the approximate date of conception, calculated from your cycle length so it reflects when ovulation likely occurred.
Copy to Clipboard
Copy a tidy summary of your due date, conception date, current progress, and days remaining in one tap.
Private by Design
All calculations happen on your device, and your last date, mode, and cycle length are saved locally for your next visit.
Frequently Asked Questions
How is my due date calculated?
The calculator uses Naegele's rule, the standard medical method: it adds 280 days (40 weeks) to the first day of your last menstrual period. If you enter a conception date or a known due date instead, it works back to an equivalent LMP and applies the same formula.
How accurate is a due date?
A due date is an estimate, not a deadline. Only about 5% of babies arrive exactly on it; most are born within two weeks before or after. An early-pregnancy ultrasound dating scan usually gives the most accurate date.
How do I calculate a due date from a conception date?
Choose Conception Date and enter the day you conceived — useful if you tracked ovulation or had IVF. The calculator establishes an equivalent LMP (conception minus 14 days) and dates your pregnancy from there.
Can I calculate my due date by LMP?
Yes — that is the default method. LMP is the first day of your last menstrual period, the date most people can remember. It is the standard used by doctors even though conception happens about 14 days later, around ovulation.
Why does cycle length matter?
Ovulation usually happens about 14 days before your next period. With a longer cycle (say 35 days) you tend to ovulate later than someone on a 28-day cycle. Adjusting the cycle length in LMP mode gives a more personalized ovulation and due-date estimate.
How many weeks pregnant am I?
Pregnancy weeks are counted from the first day of your last period, not from conception. The calculator shows your current week and day on the progress bar, so at "4 weeks pregnant" you are roughly at the time pregnancy can first be detected.
What do the milestone statuses mean?
Each of the 10 milestones is marked passed (you have already reached it), current (you are at or near it now), or upcoming (still ahead). Notable ones include the viability threshold at week 24 and full term starting at week 37.
Is my data private?
Yes. Every calculation runs in your browser, and your date, mode, and cycle length are stored only in your device's local storage — never sent to a server. Clear your browser data anytime to remove it.
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