Well... I've not used one in a number of years, but he last one I had used (which was old even back when I did last use it) seems no longer on the web... but I am aware of a couple others...
Note that supposedly if you use Windows 10 or 11, you can actually do this to a limited degree with Microsoft Photos, but it does so by making you add all the pictures to its source list and letting it scan every image into its database. I've never tried that, as while I use Photos to view images sometimes, do not ever use it as a source repository.
I've not used them... but three come to mind that are supposedly free...
Auslogics Duplicate File Finder
-
https://www.auslogics.com/en/software/duplicate-file-finder/
Awesome Duplicate Photo Finder
-
https://www.duplicate-finder.com/photo.html
VisiPics
-
https://visipics.info
Note: While as I've said I've never used the one above, I have used some Free versions of Auslogics software in the past... the ones I've used have been good, but do have offers during installation and also popups and offers for versions while using you do have to pay for... just make sure to always answer no or deselect them...