About Portable Markdown

One file. Goes everywhere.

What it is

Portable Markdown is a single-file-first Markdown toolkit. One .mdx document embeds text, images, attachments and Mermaid diagrams into a single file as Base64 — no external dependencies, trivially shareable, backup-friendly and git-ready.

Three ways to use it

ModeDescription
Static Web EditorPure client-side, no login, data never leaves your browser.
Cloud EditorGoogle sign-in, documents auto-save to the cloud.
Desktop AppsNative apps for Windows / macOS / Linux, fully offline.

Privacy

The static web editor never uploads your data; the desktop apps work fully offline; the cloud editor only saves your documents after Google sign-in. You always choose the mode that best fits your privacy needs.

Built on

Built on Cloudflare Workers + Hono, with D1 for metadata and R2 for content, and Better Auth (Google / GitHub) for auth. Rendering uses marked + DOMPurify + highlight.js + mermaid.

Links