Similar vs duplicate photos: which should you clean first?
See the difference between exact duplicates and visually similar shots, and use the safest workflow for each group.
Duplicates are the simpler category
Apple Photos can identify duplicate photos and videos and offer to merge them. This is a strong first step because the items represent the same or substantially matching content, and the system preserves relevant information in the merged result.
Similar photos require judgment
A burst, repeated portrait, or several frames of the same scene may look alike while preserving different expressions, focus, motion, or composition. There is no universally correct image to keep. Compare them as a group and zoom in before deciding.
A safe order
Start with exact duplicates, then obvious screenshots and failed shots, then review similar groups. Leave emotionally important events until last. Tools such as LessPhoto can make grouping and comparison faster, but the keep-or-delete decision should remain yours.
If Apple Photos does not show Duplicates yet, the phone may still be indexing the library. Detection can require the device to be locked and connected to power.