Enter your last period date and instantly see your pregnancy week, due date, baby size, and what's happening right now.
New pregnancy guide: Learn how weeks are counted, what each trimester means, and how to interpret your calculator results for better preparation and planning.
Read the full guide
Use the first day your period began. Don't worry if you're not 100% sure — an approximate date works fine.
Most cycles are 28 days. Adjust if yours is shorter or longer.
Your due date will be used to calculate how many weeks you are.
Baby Growth Curve
This chart visualizes the average length of the baby from week 1 to 40. Values are based on standard clinical averages.
Pregnancy Week by Week
Tap any week to see baby's development, size, and what to expect. Your current week is highlighted.
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Understanding Your Pregnancy Weeks
Pregnancy is measured in weeks from the first day of your last menstrual period (LMP) — even though fertilisation actually occurs about two weeks later. This means that when your period is "late" by one week, you are technically already 5 weeks pregnant.
A full-term pregnancy lasts between 37 and 42 weeks. Your estimated due date (EDD) is calculated as 280 days (40 weeks) from your LMP. The due date is based on Naegele's rule, which adds 9 months and 7 days to your LMP.
🌱 First Trimester (Weeks 1–12)
All major organs begin forming
Morning sickness often peaks at week 8–10
Miscarriage risk is highest — but drops sharply after week 12
12-week scan (dating scan) confirms due date
Most couples share news publicly after week 12
🌸 Second Trimester (Weeks 13–26)
Nausea usually eases — the "golden trimester"
Baby movements felt from around week 18–20
20-week anomaly scan checks all organs in detail
Gender can often be determined at the 20-week scan
Bump becomes clearly visible
🎀 Third Trimester (Weeks 27–40)
Baby gains most of its weight in these weeks
Braxton Hicks contractions become more frequent
Sleep becomes more difficult — use a pregnancy pillow
Baby "drops" (engages into pelvis) around week 35–36
Weekly OB-GYN or doctor checkups from week 36
📋 Key Antenatal Appointments
Week 8–10: First prenatal appointment (booking checkup)
