Undo Merging Duplicates - ApplePhotos

To be able to undo a merge, make a copy of yur Photos Library before merging duplicates. Then you can simply replace the library with the merged pairs by the copy of your library you have saved, if you do mat like the result. But resoring the librray from an earlier copy will only work, if you are not using iCloud Photos. If your Phtos Library is in iCloud, you would have to wipe iCloud to remove the results of the merging, and you cannot do that, if you have been using iCloud Photos and your only copies of your photos are in iCloud. With an optimized iCloud Photos Library I would not use the merge function, but do the merging of duplicates manually.

Hello Infinite3Ent,

It sounds like you want to know if you can undo a merge of your photos. We know how important this is for you, and you’re in the right place for answers. There isn't an undo merge option. However, if you have a Time Machine backup prior to the merge you can restore your photos from that point. You can leave feedback about this on the Apple Product Feedback page. More info about restoring from a Time Machine backup can be found here: Restore your Mac from a backup - Apple Support

Farewell!

Hello Infinite3Ent,

The second option if you are not using iCloud Photos was mentioned, restore your Photos library from a Time Machine backup.

More info about restoring from a Time Machine backup can be found here: Restore your Mac from a backup - Apple Support

Since that will take some time, you can also contact Apple Support to look into this further with you: Get Support

Thanks.