Buy this one! Better than the alternatives. Advice below.

This is the only duplicate finder that I could tune enough to find *all* of my duplicates. Some of the other apps also use complex image recognition (including file size, dimensions, time shot, histogram comparison, etc.), but this one has more/better options and a much better interface. I had to manually approve a lot of the duplicates because in order to catch all of them I was also catching very similar (not identical) photos, but this sped up the process immensely.

If you’re having trouble finding all of your duplicates note that different search parameters will find different *kinds* of duplicates. I had to try about 6 different approaches before I could eventually get them all. There’s no one perfect algorithm for finding all duplicates, so stay vigilant and open-minded!

morgansutherland about PhotoSweeper