Free, open-source file server in a single file: share folders by link
copyparty is a free, open-source file server that fits in a single file. Run it on a computer, share the link, and anyone with a browser can browse the folders you expose, download files, and upload things back if you allow it. No account, no client app, no cloud in the middle. It is MIT-licensed, runs on Windows, macOS and Linux, and the current release is v1.20.26, published on October 14, 2026.
The modest premise hides a deep toolbox: resumable uploads, per-user and per-folder permissions, WebDAV, SFTP, FTP and TFTP, zeroconf discovery on the local network, and optional media indexing with thumbnails. You can ignore all of it. A server that simply serves the right folder is already doing the useful work: handing somebody files without parking them in a third-party account first.
In our test we installed the Python package on Linux and served a folder over HTTP: the browser listing appeared immediately, a GET returned a test file's exact contents, and a PUT upload answered 201 with the roundtrip download byte-identical. We exercised the server core locally and did not measure transfer speeds. The trade-off to know before sharing a link widely: the files are only reachable while your machine is on and the server is running.
Featured in our discovery: copyparty: Your Files, Your Rules
One small download turns any computer into a file server; no installer, no service to configure.
Visitors browse, download and upload from any web browser; no matching app needed on their side.
Interrupted transfers resume where they stopped, even for multi-gigabyte files.
WebDAV, SFTP, FTP and TFTP alongside HTTP, with per-user and per-folder access rules.
Yes. MIT-licensed and open source; no account, no ads, no paid tier.
No. They open the link in any web browser and can download (and upload, if you allow it) from there.