Explore Our Other Free Tools
Enter your last period date and instantly see your pregnancy week, due date, baby size, and what's happening right now.
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.
This chart visualizes the average length of the baby from week 1 to 40. Values are based on standard clinical averages.
Tap any week to see baby's development, size, and what to expect. Your current week is highlighted.
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.
Explore Our Other Free Tools
