Free Pregnancy Tool
Pregnancy By Week
Enter your due date or last period. We find your week and give you a short, general look at this stage of pregnancy.
General information only, not medical advice. Ask your doctor or midwife.
How this works
Formula: Current week = (today − first day of last period) ÷ 7, rounded down, plus 1 for 'week of pregnancy'.
- Belly Weekly works out how many full weeks you are, then tells you which week you are in. At 12 weeks and 3 days you are in your 13th week.
- The notes describe what commonly happens at that stage. Every pregnancy is different.
- Your own care team's plan always comes first.
Everything is worked out in your browser. Belly Weekly does not send or store your answers.
Questions
Am I in week 12 or week 13 at 12 weeks and 3 days?
Both ways of saying it are used. You are 12 weeks pregnant, and you are in your 13th week.
Where can I read more about my week?
Belly Weekly's week-by-week guide has more for each stage of pregnancy.
What if my baby measures differently from my dates?
Babies grow at slightly different rates. Your doctor or midwife will tell you if anything needs a closer look.