Scan any folder for exact, byte-identical duplicate files of any type (documents, videos, music, archives, downloads, whole backup drives), entirely in your browser. Nothing is uploaded, nothing is installed, and you never make an account.
There is nothing to install and no sign-up. Click "Choose a Folder" and grant the page access to the folder you want to clean up. It works directly on your computer, and nothing is uploaded.
The tool first rules out every file whose size is unique (those can't have a duplicate, so they're never even opened), then double-checks the rest by comparing their actual contents, byte for byte. Duplicate groups appear live as they're found, so you can start reviewing within seconds.
Each group of identical files arrives with one copy pre-selected to keep: by default the oldest one, since duplicates are usually copies made later. A truthful badge explains why that copy won, and you can change it, switch to keeping the newest or the one in the shortest path, or dismiss a group entirely.
By default the extra copies are moved into a review folder inside your own folder, and nothing is deleted until you delete that folder yourself. Prefer permanent deletion? It's there, behind a one-time typed confirmation. You can also download a report of exactly what was removed.
Search for a duplicate file finder and every result is a desktop program you have to download and install, and most of them paywall the part that actually removes the duplicates. Installing a random cleaner utility is exactly the kind of thing that's blocked on work laptops and school Chromebooks, and exactly the kind of thing you shouldn't do lightly on a machine full of your own files.
The "online" alternatives are worse: to compare your files a website would have to receive them, which means uploading: impractical for a folder of large videos or a backup drive, and a privacy problem nobody should accept just to tidy a Downloads folder.
This tool takes neither path. It opens in a browser tab, reads the folder in place on your own computer, and uploads nothing. You can disconnect your internet after the page loads and it still works. No install, no account, no files leaving your machine.
It compares the actual contents of your files, byte for byte, not their names, not their sizes alone, not their modified dates. Two files are only ever grouped when their full contents match exactly. That means a renamed copy, a re-downloaded installer, and a file dragged from an old backup all get caught, while two genuinely different files that happen to share a size are never mistaken for each other.
Comparing every file completely would be slow. Instead it quickly rules out files that can't possibly match (anything with a one-of-a-kind size is skipped without ever being opened), then does a fast pre-check on the rest and only fully compares the handful that survive. On a normal folder it ends up reading a small fraction of your files, and it handles even very large folders and files efficiently.
Nothing is touched until you say so. When you're ready, the default action moves every copy you didn't
keep into a folder called _Duplicates_Review_ inside the folder you scanned. Each file is
copied there and verified before the original is removed, and name collisions get a "(2)" rather than
overwriting anything, so nothing is ever lost in the move.
You reclaim the space the moment you delete that review folder yourself, once you've had a look. If you'd rather skip the middle step, permanent deletion is available as an explicit opt-in with its own typed confirmation, and even then, each file is re-checked immediately before removal so a copy that changed since the scan is skipped rather than deleted.
Cleaning up photos? The Duplicate Photo Finder also catches edited, resized, and re-saved copies, not just exact ones.