How to Use Google's Search by Image as Facial RecognitionHow many times have you been at a bar, a concert, or conference and just knew you walked by someone famous — but couldn’t quite figure out who it was? Instead of wondering away for the rest of your life, Google’s new Search by Image feature might be able to help you identify your potential celebrity encounter. With Google’s new Search by Image function, you can upload an image (say, the stealth snapshot you took of the celebrity in passing) and search for visually similar images on Google’s Images index. If the person is indeed famous, Google will return a “best guess” for who the person is, as well as other images of the person.

Of course, the new feature — which just launched — is designed to help you identify things like mystery meat and the bridge you just crossed during your summer roadtrip across country. But a quick test of this feature on, as well as by using the extension¬†for Chrome, demonstrates the power of search by image as facial recognition. I was able to identify Chris Pirillo by a single photo of him on the¬†Internet, as well as see an expansive index of other photos of Chris on Google Images. Sure, you probably could only use Google’s Search by Image for only a “famous” person just for now — and unfortunately not the cute girl across the bar — but as long as somewhere on the Internet a face is indexed with the name, the power is probably limitless as to the future of facial recognition. (Just look at the feature availability in Facebook that “suggests” photo tags of your friends based on facial recognition for another indication of this future.)

To use Google’s Search by Image as Facial Recognition (at least for someone famous) visit and click on the camera button to the right of the search field. There, you can search by image by URL of the image (if it’s already on the Internet) or upload an image (such as that snapshot you took of the possible celebrity). Chrome users will also want to consider installing the Search by Image Chrome extension, which allows you to search by image directly from any image you see on the Web, making it easier to identify people (or places, or things).

What do you think about Google’s new feature to Search by Image? Is the ability to identity people by facial features helpful? Let us know your thoughts in the comments.