Ad Observer

Install For Chrome

Install For Firefox


Political campaigns spend a lot of money to reach voters on Facebook. Are they telling the truth? Are they saying different things to different people? Help hold them accountable by installing our browser plugin, which sends us the ads you see on Facebook.

How it Works Why It Matters How You Can Help Who We Are

How it Works

Ad Observer is a tool you add to your Web browser. It copies the ads you see on Facebook, so anyone, on any part of the political spectrum, can see them in our public database. If you want, you can enter basic demographic information about yourself in the tool to help improve our understanding of why advertisers targeted you. However, we’ll never ask for information that could identify you.

It doesn’t collect your personal information. We take your privacy very seriously.

Online ads are usually seen only by the audience the advertiser wants to target, and then they disappear. This makes it difficult for the public to monitor them and hold advertisers, including political groups, accountable. While platforms have developed some transparency libraries for political ads, these libraries are missing many political ads and often don’t include vital information like ad targeting. This isn’t a partisan issue. We think it’s important for our democracy to check what politicians of all stripes are saying.

You can learn more about how political campaigns and interest groups are seeking to influence your vote at our Ad Observatory.


How You Can Help


  1. Go to this link. It will open a new tab that takes you to the Firefox Add-ons store.
  2. Click the blue button that says + Add to Firefox. You may see a small window that says “ Firefox prevented this site from asking you to install software on your computer.” Please click the blue Allow button.
  3. You will then see a window that says “Add Ad Observer?” and asks for your permission. This is a disclaimer Firefox requires us to use, but we promise that the only thing we are accessing is the ads you see on Facebook. If you’re OK with that, click the blue Add button.
  4. Another window will tell you Ad Observer has been added to Firefox. Click OK.
  5. You’ll see the Ad Observer icon in the top right corner of your browser.


Who We Are

AdObserver is a project of the Online Political Transparency Project at New York University’s Tandon School of Engineering. You can read more about us here: . This extension was originally developed by researchers from the Algorithmic Transparency Institute, Quartz, New York University, and the University of Grenoble. Technical advice was also provided by ProPublica, WhoTargetsMe, and The Globe And Mail.