Facebook wants to know as much as possible about you.

The US social network is constantly tracking information about its users – however, most users will not be aware of just how much data it can siphon from a single photograph.

Facebook hints at how much data it is able to detect when it suggests people who might be in the photograph, prompting you to tag their faces.

But in reality, the California-based social network is tracking much more than just faces.

When you upload a photo on Facebook, the social network scans the image and detects how many people are in the photograph, and whether it was taken indoors or outside.

Facebook is also able to identify humans, animals and inanimate objects.

It is not always accurate, but the social network is able to differentiate between people who are standing, or sitting down.

To find out exactly what Facebook is reading into your photos, software developer Adam Geitgey has created a useful Chrome browser extension that reveals the data Facebook is collecting from your images.

Show Facebook Computer Vision Tags reveals data that Facebook usually keeps hidden from its users.

The free Google Chrome extension can be downloaded from the Chrome extension store.

Facebook has implemented object recognition technology since April 2016, a spokesperson for the company told nigerianelitesforum.com

Facebook says the data is useful for people who use screen readers – for example somebody with a visual impairment – as it allows the social network to provide a richer description of what’s in any given photo on the site.

Dubbed Automatic Alternative Text, the tool is available in 20 different languages on Facebook, including English, French, German and Spanish.

Facebook has not revealed whether the data collected from images is used to customise its targeted advertising.

The news comes as a report from ProPublica delved into the extent of Facebook's data collection policies.

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Facebook founder, Chairman and CEO Mark Zuckerberg, center, rings the opening bell of the Nasdaq stock market, Friday, May 18, 201
The New York-based investigative non-profit revealed the vast network of third-party data bought by Facebook in order to uncover even information more about its users.

For example, the California-based company first signed a deal with Datalogix to keep tabs on consumer spending behaviour back in 2012.

However the report by ProPublica makes it abundantly clear just how much visibility Facebook has into your life – online and offline.

Facebook currently provides a staggering 29,000 individual categories to its advertisers.


These allow advertisers to drill-down and target specific groups amongst the 1.79 billion monthly active users.

Of those 29,000 categories, Facebook says 600 come from third-party data providers.

According to the research conducted by ProPublica, the majority of this data from commercial data brokers is financial.

It allows advertisers to single-out Facebook users in categories including, "total liquid investible assets $1 - $24,999", "people in households that have an estimated household income of between $100K and $125K", or even "individuals that are frequent transactor at lower cost department or dollar stores".