How to Find and Delete Duplicate Files in Windows 11

This guide covers both. It starts with what Windows itself can do and exactly where each method runs out, then walks through finding and removing duplicates across every drive on a Windows 11 PC with Duplicate File Detective. Everything here applies unchanged to Windows 10.

Does Windows 11 have a duplicate file finder?

No, and the features that sound as though they should help do something narrower:

• File Explorer searches and sorts a folder tree by name, size, and date. It can show you two files with the same name and size, but it cannot tell you whether their contents match, and it only looks at one location at a time.
• Storage Sense and the Cleanup recommendations page under Settings › System › Storage remove temporary files, empty the Recycle Bin, and list large or unused files. They never compare one file with another.
• OneDrive keeps one copy of each file in the cloud, but does nothing about the copies you have made of it on disk, and its Files On-Demand placeholders complicate scanning (see the FAQ below).
• PowerShell ships with everything needed to hash files and group the results. It is the one genuinely useful manual method, and it is covered next.

Finding duplicate files in Windows 11 by hand

File Explorer: quick, but only for the obvious cases

Open the folder, switch to Details view, and sort by Size, then by Name. Copies made by a careless drag or a repeated download sit next to each other - the same name with (1) or - Copy appended, the same size. The search box narrows the field: kind:picture size:>10MB lists only large images, and *.pdf only PDFs.

This finds duplicates that were made in place. It misses the same photo saved under a different name, the same document filed in two folders, and everything on a second drive. And a matching name and size is a hint, not proof, that two files are identical.

PowerShell: exact, and honest about its limits

Windows PowerShell can compute a SHA-256 hash for every file under one or more folders and group files whose hashes match. Grouping by size first means only files that could possibly be duplicates are ever read in full:

Get-ChildItem -Path "$env:USERPROFILE\Pictures", "D:\Backup" -File -Recurse -ErrorAction SilentlyContinue |
    Group-Object Length | Where-Object Count -gt 1 |
    ForEach-Object { $_.Group } |
    Get-FileHash -Algorithm SHA256 |
    Group-Object Hash | Where-Object Count -gt 1 |
    ForEach-Object { $_.Group.Path; "" }

Change the two paths on the first line to the folders or drives you want compared, run it, and each blank-line separated block of paths is one set of identical files. This is a real duplicate finder, and it is exact: two files with the same SHA-256 hash have the same contents.

What it does not do is the rest of the job:

• It reads every candidate file in full. On a few thousand files this takes a minute; on a photo library or a second drive it takes as long as copying them, and it starts over from scratch each time you run it.
• It shows paths, nothing else. No thumbnails, no dates, no way to see which of five copies of a photo is the full-resolution original.
• It does not choose or delete. Removing the copies means editing the output into Remove-Item commands by hand, with no Recycle Bin unless you script that too, and no undo.
• It only matches exact copies. A resized photo, a re-saved document, or the same song ripped at a different bit rate all have different bytes and different hashes.
• It forces cloud-only OneDrive files to download, because hashing a placeholder means reading it.

For a single folder pair, the script is enough. For the situations most people are actually in - years of photo imports across two drives and a phone backup folder, a Documents library copied to an external drive "just in case", a music collection ripped twice - the manual method runs out at exactly the point where the volume makes a tool worth having.

How to find and delete duplicate files in Windows 11 with Duplicate File Detective

Duplicate File Detective does what the script does - confirms duplicates by content checksum, with byte-for-byte verification available - and then the part the script leaves to you: it scans every drive and folder you name in one pass, groups the matches, shows you each group with previews, applies your keep rule across all of them at once, and deletes to the Recycle Bin. Hashes are cached, so a repeat scan next month only reads files that have changed.

1. Start the Project Wizard and choose how to match. Open Duplicate File Detective and click Project Wizard on the Home tab. Choose the Checksum template, which matches on name, size, and a content checksum, or Strong Checksum if copies may have been renamed - it matches on size and content alone.
2. Add every drive and folder you want compared. Add your user folders, a second internal drive, an external drive, a NAS share - as many search paths as you like. Copies scattered across them are all compared against each other in a single pass, which is the step manual methods cannot do.
3. Accept the file type filter and run the search. The wizard proposes a file type filter based on the template. Accept it, or narrow it to documents or pictures for a first pass, then click Finish. Files are grouped by size first, so only files that could possibly match are ever hashed.
4. Review the duplicate groups. Each group in the results report holds files with identical content. Sort by size and start at the top - a few large groups usually account for most of the recoverable space. Select any photo and the Compare Images pane shows the whole group as thumbnails.
5. Mark the copies to remove. Tick files by hand, or let SmartMark apply one rule to every group at once: keep the newest, keep the oldest, keep the copy in a chosen folder, or mark everything outside a master path. SmartMark always leaves at least one copy unmarked in each group.
6. Delete to the Recycle Bin, or move or zip instead. Choose Delete with the Recycle Bin option on, or move the marked files to a holding folder or zip them if you would rather keep a way back. The Duplicate File Manager lists exactly which files will be affected before anything happens.

The Quick Start topic in the online help walks through the same first scan screen by screen, and the product tour shows each step of the process.

Deleting duplicate files in Windows 11 safely

Windows is unforgiving about a few locations, and a duplicate file finder will faithfully act on whatever you point it at. Three habits cover almost all of the risk:

• Scan your own data. Pictures, Documents, Music, Videos, Downloads, and your backup and external drives. Leave Windows, Program Files, and ProgramData out - applications routinely keep the same file at several paths and expect to find it at each one. Every new project starts with these exclusions in place, and a protected file types list keeps executables out of the results.
• Delete to the Recycle Bin. It is the default, and it is the one safeguard that reverses a mistake. It is not available on network shares or some removable media, where deletions are permanent, and it is finite, so empty it deliberately rather than letting it overflow.
• On the first pass, zip or move instead of deleting. The space is recovered either way. Delete the archive or the holding folder a few weeks later, once nothing has turned out to be missing.

Which copy to keep, and what to do when something else depends on the path you removed, are covered in Is It Safe to Delete Duplicate Files?

Windows 10, and older versions

Nothing above is specific to Windows 11. File Explorer sorting, Storage Sense, and the PowerShell script behave the same way on Windows 10, and Duplicate File Detective supports Windows 11, 10, 8, and 7 SP1 as well as Windows Server 2012 R2 through 2025. If you are cleaning up a file server rather than a PC, the network shares and file servers guide covers ownership reporting and scheduled scans.