I built an offline-first Markdown editor that runs as a single HTML file

#webdev #html #opensource #productivity

Most Markdown editors today assume cloud sync, Electron, or heavy installations.

I wanted something simpler.

I wanted a Markdown editor that:

Works fully offline
Opens local .md files directly
Saves back to the original file
Requires no account, no sync, and no network calls

Demo Video

Watch the demo video on GitHub:

https://github.com/user-attachments/assets/00d80cbc-ca93-4cfd-86d3-5299895d06b7

So I built offline-md-editor-viewer.

It runs as a single HTML file, which means it works on Windows, Linux, and macOS.

I also built a desktop version using Tauri, but both versions share the same frontend.

Main features

Live preview while editing
Folder tree support
Dark / Light theme
Local file editing and overwrite save
Privacy-focused design

GitHub:
https://github.com/ishizakahiroshi/offline-md-editor-viewer

I'd love feedback from developers who work with local notes, docs, or markdown files.

Top comments (6)

KamalMostafa • May 5

FYI, Both Firefox and Edge.

Hiroshi Ishizaka • May 24

Using the source HTML without the lib/ folder (most likely)

If you open the source file apps/browser/offline-md-editor-viewer.html without the lib/ folder, the script tag for
lib/marked.min.js fails silently, leaving marked undefined.

The single-file HTML inlines marked, so this issue should not occur — but it will happen if someone downloaded only the HTML file
from the GitHub Raw page or similar, instead of using the release ZIP.

Thank you for trying it out!