Duplicate File Finder
Find identical files by content, not by name.
Duplicate File Finder compares the files you choose by content, not by name. Files with a unique size are ruled out without being read; the rest are hashed with SHA-256 and grouped, showing how much space each group wastes. It can only see files you pick, it uploads nothing, and it deletes nothing.
Loading Duplicate File Finder…
Runs entirely on your device. No file or text you enter here is uploaded. How to verify it.
How to use Duplicate File Finder
- Choose a folder or a set of files, or drop them on the page.
- Wait while each file is hashed; progress is shown as it goes.
- Review the groups and export the list of duplicates.
Questions about Duplicate File Finder
Can it scan my whole drive?
No, and no website can. A browser can only see files you explicitly choose through a file picker or drop onto the page. That is a security boundary, not a limitation of this tool, and any web page claiming to scan your disk is not doing what it says.
Does it delete the duplicates?
No. It cannot write to your disk and would not be the right thing to do if it could. It shows you what is duplicated and lets you export the list, so you can delete with your file manager where you can see what you are removing.
Why compare contents instead of names?
Because the copies that waste space are usually the ones with different names: "report final.pdf" and "report final (2).pdf", or the same photo imported twice under different timestamps. Matching by name misses exactly the files you are looking for.
Can two different files have the same hash?
For SHA-256, not in any practical sense. A deliberate collision is a serious cryptographic result and has never been achieved for this algorithm; an accidental one will not happen. Two files with the same SHA-256 are the same file.
Is anything uploaded while hashing?
No. Hashing uses the browser’s Web Crypto implementation on your device, reading each file in chunks so a large one does not exhaust memory. Nothing is sent, which is the point — the files people deduplicate are their own documents and photos.
Does it really read every file?
No, and that is deliberate. Two files of different sizes cannot be identical, so a file whose size is unique in your selection is never opened at all. Only the files that share a size get read, and the tool reports how many bytes it actually had to look at.
Is Duplicate File Finder really free, with no limits?
Yes. There is no account, no daily cap, no file-size tier and no watermark, because there is no server cost to recover. The site is funded by clearly disclosed partner recommendations on the Partners page, never by metering the tools.
Are my files or text uploaded when I use Duplicate File Finder?
No. Everything is processed by JavaScript running in your browser, on your device. You can verify it: open your browser's developer tools, switch to the Network tab, and use the tool. You will see no request carrying your data — because there is nowhere for it to go.