XnView has a handy feature called “Find Similar Files”. It actually means files, not just finding duplicate images, although it’s not well-designed for non-image files.
First, you add the folders you want to involve in your search, and then select the parameters. Surprisingly, it doesn’t take that long to run. If you want to find exact duplicate pictures, set the ‘similarity’ at 100%. If you want the same pictures that you may have in different sizes, set the similarity factor lower.
It will bring up a screen with your results. Sometimes it will show more than one duplicate in the lower frame which just goes to show how confused you’ve become with your photo filing. But sometimes you have duplicate files for a good reason. The photos below are not duplicates at all; one’s a JPG and one’s a GIF being used in a specific project.
You may find duplicate photos with nothing but different names. This may finally convince you to decide on a naming convention. As with most everything, I find simplicity works best. Decide on something and then do it.
Another one you can try that covers all file-types is called Easy Duplicate Finder. It’s not the most ingenious layout I’ve ever seen with its teeny-tiny folder browser in the top left corner, but it’s quick and it works and it’s free. It will generate a nice color-divided list with file sizes and modified dates to help you decide if they’re duplicates. Then you can move them to another folder for double-checking or delete one of each directly.
If you like that one, you might like Duplicate Cleaner even better. You can click on file names and they’ll open for viewing. It also has an image preview window that works on JPGs, (not TIFFs).
If anyone has a favorite program for finding duplicate files, please let us know.