What TinEye does
TinEye creates a compact digital fingerprint of the image you upload, paste or link, then compares it with the fingerprints of the billions of images it has crawled from the web. It ignores file names and metadata, and it finds exact copies as well as versions that have been cropped, resized, color adjusted, heavily edited or slightly rotated. Results can be sorted by best match, most changed, biggest image, or newest and oldest crawled (the date TinEye found a copy, not the date it was published), and images from stock photo sites and collections such as Wikipedia, Flickr and NASA are tagged so you can spot the likely original.
TinEye does not recognize faces or the contents of a photo. It cannot find different pictures of the same person or object, only copies of the picture you searched, and it does not typically index social media. That makes it the right tool for questions like "where else is this exact profile photo used?" and the wrong one for finding other photos of a face. TinEye says it never adds your uploaded image to its index, keeps it only long enough to show results, then deletes it. Browser extensions for Chrome, Firefox, Edge and Opera let you right-click any web image to search; there is no mobile app, but the website works on phones.
