How to find and delete duplicate files on a Mac
Updated 2026-10-15
macOS has no built-in tool that finds duplicate files in Finder. You can narrow the search by hand, but the only reliable test is whether two files have identical contents, not whether they share a name.
Check Photos first
If your duplicates are pictures in the Photos app, open Photos and look under Utilities in the sidebar for Duplicates (macOS Ventura and later). It lists identical and near-identical items and lets you merge them. This only covers your Photos library, not files in folders such as Downloads or Documents.
Narrow it down in Finder
- In Finder, choose File, then New Smart Folder.
- Click the plus button and add a Kind or File Size rule, for example Kind is PDF.
- Switch to list view and sort by Name or Size.
- Look for copies such as report copy.pdf or report (1).pdf with the same size.
This finds likely candidates, but a matching name and size is only a hint. Two files can share both and still differ, and real duplicates are often named differently.
Compare contents instead
A tool that reads file contents can tell real duplicates from look-alikes. FileSift finds identical files and look-alike photos, always keeps one copy in each group, and checks the files again just before anything moves. Files that are stored only in iCloud are shown but never treated as duplicates, so nothing is downloaded in the background.
Delete safely
Move the extras to the Trash instead of deleting them straight away, and empty the Trash only after you have checked that the copy you kept opens. Leave the insides of app bundles and the Photos library alone; manage those from their own apps.
Common questions
Is a file with the same name always a duplicate?
No. Two files can share a name and differ in content, and true duplicates are often named differently. Compare size and contents before deleting.
How many copies should I keep?
Keep exactly one in each group. FileSift always keeps one copy and moves the others to the Trash.