Weeks to Months Converter

Wondering how many months along you are? Type in your pregnancy weeks (and days if you know them) to see months, weeks left over, and which trimester you're in. This is general information, not medical advice.

Weeks pregnantA whole number from 1 to 42.Extra days (optional)0 to 6 days on top of the weeks.

That's about

3 months, 0 weeks

84 days total

Trimester

First trimester

1st: weeks 1–13 · 2nd: weeks 14–27 · 3rd: week 28+

General information, not medical advice.

How it works

Enter how many weeks pregnant you are. If your provider gave you a week-and-days figure like "24 weeks 3 days," add the extra days too.

We use the common rule of 4 weeks to a month, then show the leftover weeks and days. That's why about 40 weeks works out to roughly 9 months.

We also show your trimester: weeks 1 to 13 are the first trimester, weeks 14 to 27 the second, and week 28 onward the third.

Frequently asked questions

Why doesn't 40 weeks equal 10 months? +

Calendar months are a bit longer than 4 weeks. Counting 4 weeks per month, 40 weeks is 10 'four-week months,' but in real calendar months a full-term pregnancy lands at about 9 months.

Which weeks belong to each trimester? +

The first trimester is weeks 1 to 13, the second is weeks 14 to 27, and the third is week 28 until birth. Different sources may shift the edges by a few days.

Do I need to enter the days field? +

No. Days are optional. Leave it at 0 if you only know your week. Adding the days just makes the months-and-weeks result a little more exact.