TinEye is a “reverse image search” that allows you to input an image and find places where it’s being used online. This is useful for finding out where a picture came from, or in the case of photographers, tracking who’s using your work.
I tested TinEye using an image I knew would appear elsewhere on the web: “Traffic-Stopping Accident on the Tappan Zee Bridge”. I copied the location of the image file on Flickr and pasted it into the TinEye search box. The search took a few seconds to run, and returned a short list of blogs using my photo.
TinEye did miss at least one hit on my photo. I knew ahead of time that my photo appears in this Gothamist post, but the post does not appear in TinEye’s results. We can’t expect everything to be perfect though, and TinEye’s results are very good (and useful).
You may be wondering how TinEye reverse image search works. Instead of using keywords and other meta data found around images, like Google Image Search, TinEye examines files based on the actual content of the image. For this reason your search results only contain exact matches, not similar images. According to their FAQ, they’ve currently indexed over 1.2 billion images.