Government surveillance garners all the headlines, but Americans are voluntarily turning over more personal information to tech companies than most government agencies could ever hope to obtain.

Case in point: Facebook has labeled the political leanings of its users with stunning accuracy by simply gathering information about them on the site. Political campaigns then pay big bucks to target their advertising at whatever slice of the electorate they want to hit.

Want to see how Facebook tags you, from conservative to moderate to liberal? The New York Times explains how:

Try this (it works best on your desktop computer):

Go to facebook.com/ads/preferences on your browser. (You may have to log in to Facebook first.)

That will bring you to a page featuring your ad preferences. Under the “Interests” header, click the “Lifestyle and Culture” tab.

Then look for a box titled “US Politics.” In parentheses, it will describe how Facebook has categorized you, such as liberal, moderate or conservative.

(If the “US Politics” box does not show up, click the “See more” button under the grid of boxes.)

The social media giant pulls this off by analyzing the pages you “like” and the content you interact with.

It could be as easy as recognizing you like pages for The Republican Party, Fox News and The Ronald Reagan Presidential Foundation and figuring you are probably conservative. Conversely, the same algorithm might recognize you like pages for Barack Obama, MSNBC and the Southern Poverty Law Center and figure you are probably liberal.

But it goes much deeper than that. Even users who are more discreet about their political ideology can inadvertently expose themselves to Facebook’s data mining operation.

Like Ben & Jerry’s ice cream? You’re probably liberal. Prefer Blue Bell? You’re probably conservative. Big fan of 30 Rock? You’re more likely to lean left. Prefer 24? Right. Watch the NBA? There is a greater likelihood that you are a liberal. Get into NASCAR? You are more likely a conservative. Now multiply that by every single page you like on Facebook and it doesn’t take long to see how Facebook has you pegged.

Facebook has also replaced the traditional “like” button with “reactions” that include other emotions, and they’re tracking your every interaction with a piece of content — whether it’s a photo, text post or a link to an article — and using that data to create a profile on you.

Those profiles are the backbone of Facebook’s business model, because they are a goldmine for advertisers who want to market their products or services to the people who are most likely to buy whatever it is they’re selling. Facebook has that kind of information on 1.7 billion people around the globe, including 204 million in the United States. And they got it all with our consent.