Turning Word into Markdown without the file leaving your computer

A .docx is a zip archive. Opening it means unzipping it and reading the XML inside, and every step of that runs in JavaScript on this page — the same code the browser already downloaded when the page loaded.

There is no upload because there is nothing to upload to. The tool is a handful of static files; nothing behind it is waiting for your document. The bytes stay on the machine you're sitting at.

An offline conversion is the entire argument in one gesture: code that phones home cannot work with the phone unplugged.

Markdown is plain text. Every character of the output is on the screen in front of you, and you can read all of it before pasting it anywhere — there is no hidden layer left to trust.

A .docx is the opposite. It carries author names, an editing history, revision marks and template paths, tucked where you never see them. Converting to Markdown leaves that behind: the words come through, the buried metadata does not, because plain text has nowhere to keep it.

It uploads. Your file lands in temporary storage on someone else's computer, is converted there, and is meant to be deleted afterwards — on a schedule you can't see and can't check.

For a meme, fine. For anything under an NDA, "deleted within an hour" is a promise, and a promise is a different thing from a file that was never sent.

It's fair to name the edges. Keeping the file off the network says nothing about what you do with the result: paste the Markdown into a public gist and it's public, however it got there.

Anything already watching your own machine still sees it — a browser extension with access to the page, or malware, reads what you read. Converting locally removes the upload, not every risk. What it removes is the largest one: a copy of your document resting on a stranger's server.