Share on FacebookTraditionally you will search for an image in Google using the Google Image search. The search results are based on tags or search strings associated with the images – it doesn’t really compare or process the image itself to determine if the image you want matches similarly to the one you want. Google is fixing that problem via a new development from Google Labs: the Similar Images service.
To start searching for similar images, open the site http://similar-images.googlelabs.com then start with a search query using traditional text search. In the example below I searched for images of Moon. Like the image search in Google, it returned all significant images matching the search term.

Pick an image that you want to use as a reference. Click the “similar images” link
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