To find duplicate files on a Mac without another app, use Finder. Open the folder you want to check, choose View › as List, and sort by Name or Size: copies sit next to each other, often with "copy" or a number in their name.
To look across a whole folder, press Command-F and search by name, kind or size, then save the search as a Smart Folder to run it again later.
For photos, Photos has its own tool: click Duplicates under Utilities in the sidebar and merge them there. For songs, select one in Music and choose File › Library › Show Duplicate Items.
Before you delete anything, know two things. macOS has no built-in tool that compares every file's contents, so Finder finds likely duplicates and you confirm them. And many copies made in Finder share their space with the original, so deleting them frees almost nothing.
Find duplicate files on a Mac with Finder
Finder can't compare the contents of two files, but it can put likely duplicates side by side. For most folders, that's enough to find the copies that matter.
How do you spot copies by name?
When you duplicate a file in Finder, the copy keeps the original's name with "copy" added, and later copies get "copy 2", "copy 3" and so on. Files copied into a folder that already has one with the same name can end up with a number added when you choose to keep both.
Browsers add their own marks. Chrome and many other apps save a second download of the same file with a number, such as report (1).pdf. Safari is the exception: Apple says that when you download an item you already downloaded, Safari removes the older duplicate.
So sorting by Name in list view is the quickest first pass. The original and its copies line up one after the other.
How do you find files with the same size?
Two files with exactly the same size and kind are often, though not always, the same file. Sorting by size brings them together.
- Open the folder and choose View › as List.
- Click the Size column heading to sort by size.
- If there's no Size column, Control-click any column heading and choose Size.
- Look for neighbors with the same size, kind and similar names.
Sizes in list view are rounded, so two files that both show 2.4 MB may differ by a few bytes. Select a file and choose File › Get Info to see its exact size in bytes.
How do you search a whole folder or disk?
- Open the folder you want to check, or any Finder window, and press Command-F.
- Next to Search, choose the folder's name to stay inside it, or This Mac to search everywhere.
- Click the first pop-up menu, choose Name, then contains, and type copy.
- Click the add button to add rows such as Kind is Image, or File Size is greater than 10 MB.
A file must match every row to appear. Apple's Finder help notes you can hold Option and click the button that appears to require that any, all or none of the rows match, which lets you search for several name patterns at once.
How do you keep the search as a Smart Folder?
Click Save below the search field, give it a name, and leave Add To Sidebar selected. Apple describes a Smart Folder as a saved search: its list updates by itself as you add, change or delete files that match.
To change it later, open the Smart Folder, click the Action button and choose Show Search Criteria. A Smart Folder holds no files itself; removing a file from it in Finder moves the real file to the Trash.
What can't Finder do?
Compare contents. Two files named differently can be identical, and two files with the same name and size can differ inside. Finder has no command that checks whether the bytes match.
It also can't tell you whether a copy is a clone that shares its space with the original. Both show the same size in Finder. That's covered further down, and it changes what deleting a duplicate is worth.
| Clue | What it suggests | How to confirm |
|---|---|---|
| Same name with copy or a number | A Finder copy or a repeat download | Compare size and dates in Get Info |
| Same size and kind | Possibly the same file | Open both with Quick Look |
| Same name, different size | Different versions | Check Date Modified; keep the right one |
| Folder named copy, old or backup | A copy kept before a change | Compare the folders' contents and sizes |
| Same photo in two places | An import that copied it | Check whether Photos has it |
How to tell two files are really the same
Finding candidates takes minutes. Deciding they really are duplicates is the careful part, and it's where people delete a version they still needed.
Is the same name enough?
No. Plenty of different files share a name: every camera calls its photos something like IMG_1234, and many documents are called Untitled or Invoice. A matching name only tells you where to look.
Is the same size enough?
It's a strong hint for large files such as videos and disk images, and a weak one for small ones. Two photos from the same camera can be close in size and look nothing alike.
When two large files match to the byte in Get Info, and have the same kind and similar dates, they're very likely the same. Look at them anyway before you remove one.
How do you compare two files without opening them?
Select both and press the Space bar. Quick Look opens them together; use the arrow keys to switch between them. For photos and PDFs, you see at once whether they match.
For documents, also check the details. Select each file and choose File › Get Info: Created and Modified tell you which is older and which was edited last.
What about documents that look the same?
Be careful here. A contract, a CV or a design file often has several versions that look alike on the first page and differ further in. The copy you'd delete may be the one with the final changes.
Open both and look at the end, or at the part you'd expect to change. If in doubt, keep both and rename one so the difference is clear, such as adding "final" or a date.
What about folders that look like duplicates?
Folders named "Project copy", "Project old" or "Backup" are usually a whole folder copied before a change. Some files inside may have changed since, and others may exist only in one of them.
Open both in list view, turn on Calculate all sizes in View › Show View Options, and compare. Merge any files that exist only in the copy into the folder you're keeping before you remove the other.
Duplicate photos: the Duplicates collection in Photos
Photos finds duplicates in your library by itself. It's the only safe way to remove them, because a Photos library is a database that only Photos should change.
Where do you find duplicate photos?
Open Photos and click Duplicates below Utilities in the sidebar. If you don't see it, hold the pointer over Utilities and click the arrow that appears.
Duplicates appear there automatically. Apple notes they may take a while to show up, because Photos analyzes your photos first, and the larger the library, the longer that takes.
How do you merge duplicates?
- Click Duplicates in the sidebar.
- Select the duplicates you want to merge: one row, several rows, or press Command-A to select all.
- Click Merge with the number of items, then confirm in the dialog.
Apple says one original photo or video then appears where the duplicates were in your library. With an iCloud Shared Photo Library, choose Both Libraries from the Library pop-up menu in the toolbar first, so the view covers both.
What happens to the extra copies?
They go to Recently Deleted, where you can recover them for 30 days. After that, Photos deletes them for good. To free the space sooner, open Recently Deleted, select them and click Delete.
With iCloud Photos on, merging affects your library on all your devices. If you want to look again before anything is final, leave the copies in Recently Deleted for a few days.
Why do photos get duplicated?
Usually through importing. Photos has an importing setting, Copy items to the Photos library, in Photos › Settings › General. With it on, importing photos from a folder copies them into the library and leaves the originals where they were.
That's two copies of every imported photo: one in the library and one in the folder. Once you've checked the library has them, the folder's copies are the ones to consider removing, in Finder, after you've confirmed a backup.
Why shouldn't you delete photos in Finder?
The Photos library looks like one file in Finder, but it's a package with a database inside. Apple's guidance is not to access or change a library's contents in Finder, and doing so can damage it.
Delete and merge only inside Photos. If you want to move photos out of the library, export them from Photos first. The post on Photos taking up space covers what else the library holds.
Duplicate songs: Music's duplicate view
Music has its own duplicate finder, built for a library where the same song can turn up on an album, a compilation and a soundtrack. Like Photos, it's the right place to remove them.
How do you show duplicate songs?
- Open Music and click Songs in the sidebar.
- Select a song.
- Choose File › Library › Show Duplicate Items.
That shows every instance of that song in your library, such as the same track on an album and on a soundtrack. To see only exact duplicates, hold the Option key and choose File › Library › Show Exact Duplicate Items. Apple defines exact duplicates as songs whose song, artist, album and version are all the same.
To see your whole library again, click Done in the bottom-right corner, or choose File › Library › Show All Items.
How do you delete a duplicate song safely?
Select the copy you don't want and press Delete, then click Delete Song. Music asks what to do with the file: Keep File removes it from your library only, and Move to Trash deletes the file too, once you empty the Trash.
Don't select every result and delete them all. The duplicate view lists all copies, including the one you want to keep. Delete only the extra copies, one by one, and check the song still plays.
Where do duplicate songs come from?
Most come from importing the same files twice, or from a setting that copies files. In Music › Settings, the Files tab has Copy files to Media folder when adding to library. With it on, dragging a song into Music copies it into the Media folder and leaves the original where it was.
So a folder of music you imported may now exist twice: once in that folder and once in Music's Media folder. Once Music plays everything from its own copy, the originals outside it are the duplicates. Removing files from Music's Media folder in Finder instead leaves songs Music can't find.
| App | Where to find duplicates | What happens to extra copies |
|---|---|---|
| Finder | Sort by name or size, or search | Move to Trash; Put Back until emptied |
| Photos | Duplicates, under Utilities | Recently Deleted for 30 days |
| Music | File › Library › Show Duplicate Items | Keep File or Move to Trash |
| No duplicate view | Saved attachments are ordinary files in Finder |
APFS clones: duplicates that don't take extra space
This is the part most duplicate guides leave out, and it decides how much space a cleanup really frees. On a Mac, many copies aren't copies of the data at all.
What is an APFS clone?
APFS is the file system every current Mac uses for its startup disk. Apple's developer documentation describes a clone as a copy of a file or directory that occupies no additional space on disk.
The two files share the same data. If you change one, only the changed parts are written elsewhere, and the rest stays shared. Apple gives document copies and revisions as the example of where this saves space.
Which copies are clones?
Copies made on the same APFS disk usually are. That includes duplicating a file in Finder with File › Duplicate, and copying and pasting a file into another folder on the same disk. It's why duplicating a large video finishes almost instantly.
Copies that arrive separately are not. Downloading the same file twice, receiving it twice, or copying it from another disk makes a real second copy that takes its own space.
Why does deleting a clone free almost nothing?
Because the space belongs to both files at once. Delete the copy, and the original still uses every shared block, so almost nothing comes back. Delete the original and keep the copy, and the result is the same.
The space comes back only when the last file using that data is gone. If you edited one of the two, only its changed parts are its own, and deleting it frees just those. The post on why deleting files doesn't free space covers clones and the other reasons in detail.
Why do Finder's sizes add up to more than the disk holds?
Finder shows each clone at its full size, and a folder's size counts each one in full. A folder of clones can look several times larger than the space it really takes.
Finder has no column or badge that marks a file as a clone. The clue is a deletion that frees far less than Finder said the file took. The disk's own totals, such as the used space Disk Utility shows for a volume, don't count shared data twice.
- What Finder adds up for the five files50 GB
- Space the disk really uses10 GB
- Space freed by deleting four copies0 GB
- Five separate downloads of the same video50 GB
A worked example, not a measurement: per Apple's APFS documentation, a clone occupies no additional space until it's changed. Small amounts of metadata are left out.
What is a hard link?
A hard link is a second name for the same file, often in another folder. Delete one name and the file is still there under the other, using the same space. macOS frees it only when the last name is removed.
You rarely make hard links yourself. Some backup tools and some developer tools make them, so two entries that look like duplicates in those folders may be one file.
| How the copy was made | Shares space with the original? | Deleting it frees |
|---|---|---|
| File › Duplicate in Finder, same disk | Yes, until either is edited | Almost nothing |
| Copied to another folder, same disk | Usually, yes | Almost nothing |
| Downloaded or received twice | No | Its full size |
| Copied from another disk | No | Its full size |
| Imported into Photos or Music with copying on | No | Its full size |
Where duplicates usually come from
Knowing where duplicates come from tells you where to look first, and which copy is the spare. A few habits and settings account for most of them.
Downloads, twice
Downloading something again because you couldn't find the first copy is the most common source. Sort Downloads by name and the pairs show up at once.
Archives you've already opened are a variation: the .zip file and its expanded folder hold the same files. The post on cleaning up the Downloads folder covers what's safe to remove there.
iCloud Drive's Desktop and Documents
Turning Desktop & Documents Folders on and off is a quiet source of duplicates. Apple says that when you turn it off, your files stay in iCloud Drive, and a new Desktop and Documents folder are created locally in your home folder.
People then copy files back from iCloud Drive and end up with two sets. On a second Mac, Apple says its files go into a folder with the same name as that Mac. If both Macs had copies of the same files, both sets now sit in iCloud Drive.
Be careful deleting anything in iCloud Drive: a file you delete there is deleted on all your devices. Decide which set you're keeping before you remove the other.
Copies kept before a change
A folder copied "just in case" before an edit, a migration or a reorganization often outlives its purpose. Names such as old, backup, copy or a date are the clue.
These copies are worth comparing rather than deleting outright. The copy sometimes holds the only version of a file that later changed in the original.
Imports into Photos and Music
As covered above, importing with copying turned on leaves the originals where they were. A folder of photos already in your Photos library, or a folder of songs already in Music's Media folder, is a duplicate on disk even though each app shows only one copy.
Attachments and transfers
Saving the same email attachment twice, receiving the same file by AirDrop and by email, or copying files from a phone more than once all leave separate copies. These are real copies, not clones, so removing the extras frees their full size.
| Source | Typical duplicate | What to do |
|---|---|---|
| Repeat downloads | report (1).pdf next to report.pdf | Keep the newest; remove the rest |
| Finder copies | photo copy.jpg, Project copy | Compare; deleting frees little |
| iCloud Desktop and Documents | Two sets of the same folders | Pick one set; remember deletions sync |
| Photos import with copying on | Originals in a folder outside the library | Check the library first |
| Music import with copying on | Songs outside Music's Media folder | Check Music plays its own copy |
Decide which copy to keep
Once you're sure two files are the same, choosing which one to keep is quick. When they're nearly the same, these questions keep you from removing the wrong one.
Which location is the right one?
Keep the copy in the place you'll look for it: the project folder, Documents, or the app's library. A copy in Downloads, on the desktop or in a folder named copy is almost always the spare.
Should you keep the newest or the original?
For documents, usually the newest: check Modified in Get Info. For photos and videos, the original from the camera may be better than an edited or exported copy, which can be smaller or lower in quality.
If the two differ, they aren't duplicates. Keep both, or keep the one with the changes you want and note why.
Which copy has the better quality?
For images, select each and choose File › Get Info: More Info shows the dimensions. Keep the larger one. For videos, Quick Look both and compare, and check the sizes: a much smaller copy is usually a compressed export.
Is one of them backed up or in iCloud?
A copy in iCloud Drive is already in iCloud, and deleting it there deletes it everywhere. A copy only on this Mac may be the one Time Machine backs up. Neither rule says which to keep, but know where each one lives before you remove it.
What about copies on an external drive?
A file that exists on your Mac and on an external drive isn't a duplicate to clean up; it's a backup. Copies on another disk are real copies with their own space, and that's the point of them.
If you want the space on your Mac, keep the copy on the drive and remove the one on the Mac, but only after you've opened the drive's copy to check it works. Keep a second copy somewhere else for anything you can't replace.
When should you keep both?
When they're versions rather than duplicates, when one is in a shared folder others use, or when an app expects the file in a particular place. Deleting a file an app points to, such as a song Music plays from a folder outside its Media folder, leaves the app unable to find it.
Remove duplicates safely
Duplicates feel like the safest thing to delete, since there's another copy. That's exactly why the occasional mistake is so costly: the other copy turns out to be older, damaged, or not a copy at all.
Move them to the Trash, then wait
Move duplicates to the Trash rather than deleting them immediately, and leave them there for a few days. If something turns out to be missing, select it in the Trash and choose File › Put Back.
Then empty the Trash, and check Storage settings to see what changed. If less space came back than you expected, some of the copies were clones.
Don't remove files from inside libraries or sync folders
Photos and Music libraries, iMovie and Final Cut libraries, and the folders that iCloud Drive, Dropbox or OneDrive sync all manage their own files. Removing a "duplicate" from inside one in Finder can damage the library or delete the file on every device.
Use the app's own tool instead: Duplicates in Photos, the duplicate view in Music, and each sync app's own settings for online-only files.
What should you check in a duplicate-finder app?
Dedicated apps usually compare file contents, which is more reliable than names and sizes. If you use one, check a few things before you trust it:
- It shows you each group of duplicates before anything is removed, with a preview.
- It moves files to the Trash rather than deleting them outright.
- It leaves Photos and Music libraries to those apps.
- Its estimate of space saved accounts for clones and hard links; otherwise it can promise space that never comes back.
Should you use a Terminal command to find duplicates?
Many guides offer a command that finds files with matching contents. Even when it only lists them, the commands that follow in such guides often delete files directly, skipping the Trash, with no preview and no undo.
Finder, Photos and Music do the job with lists you can sort, preview and put back. A guide that asks you to paste a command to free space is worth closing: fake cleanup guides are a known way to install malware.
Will removing duplicates make your Mac faster?
No. Removing duplicates frees space, and only as much as the copies really used. Apps don't run faster because there are fewer files, though having free space helps when installing updates or saving large files.
A first pass, start to finish
If you've never looked for duplicates before, this order finds the most for the least risk. Nothing in it is permanent until you empty the Trash.
Start where copies collect
- Open Downloads in list view and sort by Name. Remove repeat downloads, keeping the newest of each.
- Do the same on the desktop, where screenshots and files dragged out of other apps pile up.
- Press Command-F, choose This Mac, and search for Name contains copy. Save it as a Smart Folder.
- Go through the Smart Folder with Quick Look, and move confirmed copies to the Trash.
Then let the apps do their part
- In Photos, open Duplicates under Utilities and merge what it found.
- In Music, select a song and choose Show Exact Duplicate Items with the Option key held, and remove the extra copies one by one.
- Look for folders of photos or songs you've already imported, and check each app has them before you remove the folder.
Finish with the Trash
Leave everything in the Trash for a few days, then empty it. Check Storage settings afterwards. If less space came back than the copies seemed to take, some of them were clones, and the space they shared stays with the copies you kept.
How the app does it
Wombit is a native Mac app that shows what's using your storage, explains every item in plain language, and clears it safely: Trash first, undoable and logged. Its scan covers the whole disk or any folder, reading only names, sizes and dates, and file names and paths never leave your Mac.
It doesn't have a duplicate finder. What it does is measure the way the disk does: hard links and APFS clones count once, so the map and the totals show the space files really take, not the larger sum Finder adds up.
The map is the home screen, with a list and search beside it. Search by name to find copies, select one to see what it is and how safe it is to remove, and use Quick Look and Reveal in Finder to compare files before you decide.
Libraries are explained, not picked apart. A Photos library is Managed by macOS: the app explains it and points you to Photos, and never moves it. Music's Music media folder files are Review first, since imported songs may exist nowhere else. Large files not changed in a year, a common home for forgotten copies, are Review first too, and nothing inside Documents or Desktop is ever checked for you.
Finding and explaining is free, with the map, the list, search, Quick Look, Undo and Put Back. Cleanup is PRO: one payment of $4.99 with lifetime access. Every Pro tool's review is free to open, so you see what would go and why before you buy.
Frequently asked questions
Does a Mac have a built-in duplicate file finder?
Not for files in general. Finder can sort and search so likely copies sit side by side, but it doesn't compare contents. Photos and Music each have their own duplicate tools for their libraries.
Why didn't deleting duplicate files free up space on my Mac?
Copies made in Finder on the same disk are usually APFS clones, which share their data with the original. Deleting one frees almost nothing until every copy using that data is gone. Files in the Trash also keep their space until you empty it.
How do I delete duplicate photos on a Mac?
Open Photos and click Duplicates under Utilities in the sidebar. Select the duplicates and click Merge, then confirm. The extra copies go to Recently Deleted, where you can recover them for 30 days.
How do I find duplicate songs in Apple Music on a Mac?
Click Songs in the sidebar, select a song, then choose File › Library › Show Duplicate Items. Hold Option to choose Show Exact Duplicate Items instead, which lists only songs whose name, artist, album and version all match. Click Done to see your whole library again.
Is it safe to delete files with copy in their name?
Usually, once you've checked they match the original. A copy may have been edited after it was made, so compare dates and contents first. Move it to the Trash rather than deleting it immediately, so you can put it back.
Are duplicate file finder apps safe to use?
They can be, if they show each group before removing anything and move files to the Trash. Avoid letting one remove files from inside the Photos or Music library, and be wary of space estimates that ignore APFS clones.
Which duplicate should I keep?
Keep the copy in the place you'll look for it, such as the project folder or the app's library. For documents keep the newest version; for photos and videos keep the larger, original one. If the two differ at all, they're versions, so keep both.
Sources
- Remove duplicates in Photos on Mac · Apple
- Find duplicate items in Music on Mac · Apple
- Narrow your search results in Finder on Mac · Apple
- Create or change a Smart Folder on Mac · Apple
- About Apple File System · Apple Developer
- Add your Desktop and Documents files to iCloud Drive · Apple