About
A thread you can follow.
Filum is 28 PDF tools — most running on-device, format conversion using a secure server that deletes within 60 minutes — built one at a time and verified on real documents before they appear. No account. No permanent storage. No claims that haven't been measured.
The name is the principle
Filum is Latin for thread. For centuries, important documents were bound and sealed with thread — “red tape” is literally named for it. The thread was a promise: this document is intact, and nobody has touched it. That is the standard every tool is held to: the output is exactly what you chose, and nothing else is altered.
On-device where the work can be done there
Organize, merge, split, sign, rotate, redact, watermark, and more — everything that doesn’t require a specialized conversion engine runs entirely in your browser. Your file never reaches a server. For format conversion (Word, Excel, PowerPoint, EPUB, and more), Filum uses a secure server that deletes the file within 60 minutes. No permanent storage, no profile, no account.
One verified tool at a time
A tool is listed only after it passes verification against real documents — real PDFs in a real browser, output bytes inspected, every failure path tested. There is no “basic support” and no hedged claim. If a tool can’t meet that bar in full, it isn’t listed.