If they are the exact same size, the files are considered duplicate. Even though the file names for the photos were different, it seems to find duplicates based only on size. I tried my tests on the sample photos included with Windows 7 and it worked fairly well. Go ahead and click Start Search and you’ll get the results in a pop up window. If you want to restrict the types of files scanned, then you should use the filters. By default, they are configured to search everything. If you’re only looking for duplicate files and want to find all of them, then don’t change any of the filters or settings. As you can see, everything else is self-explanatory. Next, you choose the base folder where you want the search to start from. Once you download and run it (no need to install), just click on the drop down at the very top and change the value to duplicates search. It also has a search mode called Duplicates Search. It has a ton of filters that let you search by wildcard, by file dates, by file content, by file size, by file attributes, etc. One of their tools is SearchMyFiles, which is basically a super search engine for your local files and folders.

If you’re looking for some of the most useful software tools for Windows, then NirSoft should be the first place you look.

Free app to clean up duplicate photos