Find duplicate files in a folder — without uploading anything

Pick a folder and find files that are byte-for-byte identical — merged photo backups, redundant exports, whatever's eating your disk space. Everything is hashed and compared right here in this tab.

How it works: every file's contents are hashed with SHA-256; files sharing a hash are true duplicates, no matter what they're named. Nothing is uploaded — this page makes no network requests.

How to use this tool

Use the dropzone below — that's the whole tool. (The downloaded version is the same tool as a file that opens in any browser, no install or internet needed.)
In Chrome, Edge, or Brave, click Choose a folder… and pick the folder to scan (you'll get a one-time permission prompt). In Safari or Firefox, click Select a folder's files… instead.
Wait for the scan — a progress bar shows how many candidate files have been hashed.
Review the duplicate groups. One copy in each group is marked "Keep" by default; nothing is selected for removal until you choose.
In Chrome/Edge/Brave: check the duplicates you want gone, click Delete selected, and confirm. In Safari/Firefox: click Export list (.csv) and remove the files yourself.

No folder selected yet.

Pick a folder of photos, documents, or downloads to scan for exact duplicates.

What is this page?

This is the real Duplicate File Finder — the same tool Untracked sells as a download — running free, right here in your browser. Your files are processed entirely on your own device: nothing is uploaded, no account is needed, and the page makes no network requests after it loads. You can verify that yourself: load the page, open your browser's network inspector, or even disconnect from the internet and keep using it.

Free page vs. the €5 download

Here (free): unlimited single files — one at a time, as many as you like, forever. Counted only in your own browser (localStorage): no cookies, no analytics, nothing that identifies you.

The download (€5, once): batch/folder processing, ZIP export, and the tool as a single HTML file that runs offline forever on any computer you own — even with no internet at all. Plus the commercial-use licence. Full details →

Questions people ask

Are my files uploaded anywhere?

No. The scan reads file contents inside your browser — the folder picker runs locally and no byte ever leaves your machine. Disconnect from the internet and it still works.

How does it detect duplicates?

By content, not filename: every file is hashed as it is read, and identical hashes are grouped as duplicates — so renamed copies are still found.

Is there a folder-size limit?

This free page is tuned for small folders (up to about 20 files per scan). The downloaded version scans folders of any size and adds one-click selection helpers.

What's the difference between this free page and the paid download?

The free page does unlimited scans on small folders. The €5 download removes the size cap, runs offline forever, and adds export of the duplicate report.