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Local-first · on-device

Your files stay on the thread.

filum is Latin for thread. Every tool runs inside your browser — your document is read, worked on, and handed back without ever leaving your device. Held on the line. Never sent.

No upload No account Nothing stored
on device
The toolkit

Everything you do to a document.

22 tools, each running entirely in your browser — so the work is private by default, not by promise.

Why on-device

The only document tool that can't see your files.

Other converters upload your document, then ask you to trust a deletion promise. Filum removes the need for trust — there is nothing on the other end.

Nothing is uploaded

Every tool executes in this browser tab. The file is read from disk, worked on, and saved back — it never travels to a server, so it can't be intercepted or logged.

Nothing is stored

There is no copy on a server to leak, sell, or forget to delete. Close the tab and nothing of your file remains anywhere but your own machine.

Nothing to wait for

No upload-and-download round-trip — the work starts instantly and finishes at the speed of your device, not your connection. No account, no email.

Your documents, kept to yourself.

Open a file and watch the work happen — without a single byte leaving your device.

Filum — File conversion that earns trust