Pregnancy Week Tracker
Enter your last period and we'll tell you exactly how many weeks pregnant you are, your trimester, and what's happening this week.
We'll calculate your gestational age and find your week info.
What "weeks pregnant" really means
Gestational age is counted from the first day of your last menstrual period — not from conception. This is a clinical convention, not a mistake. Period dates are something most people know precisely; conception dates often aren't. So the first two weeks of "pregnancy" are technically before you've even ovulated.
The three trimesters
- First Trimester (1–13 weeks)
- Second Trimester (14–27 weeks)
- Third Trimester (28–40 weeks)
Each week explained
Click any week below to see what's happening with your baby and your body that week, plus tips for managing common symptoms.
Frequently asked questions
How is pregnancy week counted?
Standard clinical practice counts pregnancy weeks from the first day of your last menstrual period (LMP), not from conception. So when your provider says "you're 8 weeks pregnant," conception was actually about 6 weeks ago.
What week is the first trimester?
The first trimester runs from week 1 through week 13. The second trimester is weeks 14–27, and the third is 28 through delivery.
How many weeks is full-term?
Full-term is 39 to 40 weeks, 6 days. "Early term" is 37–38+6, "late term" is 41–41+6, and "post-term" is 42+.
Can I really track my pregnancy this precisely?
Yes for the math, but remember every pregnancy varies. The dates the calculator gives are estimates — your ultrasound dating is more accurate, especially in the first trimester.
More tools
Due Date Calculator
Estimate your delivery date by last period or conception date. Naegele’s rule plus cycle adjustments.
Contraction Timer
Tap once to start, once to stop. Tracks duration, frequency, and pattern over time.
Ovulation Calculator
Find your fertile window based on your cycle length. Plan or avoid with confidence.
Baby Name Generator
Filter by origin, style, length, and starting letter. Boys, girls, and unisex.
Growth Percentile
Plot your baby’s weight, length, and head circumference against WHO percentile curves.