Wear Justin Bieber's face, for free!

Have a dream to look like Brad Pitt or Rihanna? Go to a real-time face substitution app using your webcam to fulfill your desire.

An Oslo-based computer science artist Audun Mathias Oygard has designed a unique face substitution app using the JavaScript library clmtrackr.

Once on the Oygard website (http://auduno.github.io/clmtrackr/examples/facesubstitution.html), you can choose from a fascinating list of celebrities you would like their faces to wear on.

To begin with, you have George Clooney, Rihanna, Bill Murray, Kim Kardashian, Barack Obama, Justin Bieber, Kanye West, and many more to try.

It's simple. Just log on, allow access to the webcam and sit still while the facemodel sizes them for a mask, said media reports.

"It's a really eerie effect to 'wear' someone else's face when you're mostly used to seeing your own face in the mirror," Oygard was quoted as saying.

"I noticed that I subconsciously changed my facial expressions depending on which face I was 'wearing', which was kind of funny," he added.

According to Oygard, the app works best and is a lot less glitchy than previous face substitution apps.