Separate identical from similar
Exact duplicates have matching file contents. CleanPanda uses SHA-256 to group exact copies. Similar photos are a separate suggestion: a crop, edit or lower-resolution export may still be worth keeping.
Review names, paths, dates and previews. Decide which copy belongs in the folder you actually use. A familiar filename alone does not tell you which version is the original.
Keep one known copy
CleanPanda keeps at least one file in each duplicate group. Check that the remaining copy is available where you need it and that apps or projects do not depend on a different path.
Cloud-only placeholders and backup copies need separate consideration. Do not assume that another device or a backup contains a usable copy without checking it.
Understand the space and the way back
On APFS, clones can share physical storage. Adding the displayed file sizes does not always tell you how many bytes removal will recover. Replacing copies with clones is offered only where the app supports it.
Move only the copies you have reviewed to the Trash. Open the copy you kept before emptying the Trash. Activity can restore a removed item while it remains in the Trash.