Type on one side. The other side follows.
A two-pane editor that converts between HTML and Markdown live, in both directions. Edit either format and the other updates as you type.
GitHub-flavored Markdown (tables, strikethrough, task lists), a sanitized rendered preview, file open/save, drag-and-drop, and conversion options — all in a single browser tab.
The Dual HTML & MD Editor is a bidirectional converter between HTML and Markdown.
The left pane holds HTML, the right pane holds Markdown; typing in either one converts and updates
the other after a short pause. Everything runs entirely in your browser — the only network traffic
is loading the open-source conversion libraries from public CDNs on first visit. Your content is
autosaved to your browser's localStorage and never transmitted anywhere.
.html/.htm files load into the HTML pane, .md/.markdown/.txt files into the Markdown pane..txt into the HTML side.notes.md, save notes.html).| Button | Action |
|---|---|
| 📂 Open | Open an .html, .htm, .md, .markdown, or .txt file into the matching pane |
| 💾 Save .html | Download the HTML pane as a file |
| 💾 Save .md | Download the Markdown pane as a file |
| ⇄ / → / ← | Cycle the sync direction: both ways, HTML → MD only, or MD → HTML only |
| ⚙ Options | Open the conversion options panel |
| 👁 Preview | Toggle the rendered preview pane |
| 🗑 Clear | Empty both panes (also clears the autosave) |
By default the editors sync both ways (⇄). Clicking the arrow button locks the conversion to one direction: in → mode only HTML → Markdown runs, so you can hand-polish the Markdown output without your edits being overwritten by a re-conversion — and the reverse in ← mode. The locked pane still autosaves while you type.
| Option | Effect |
|---|---|
| Heading style | ATX (## Heading) or Setext (underlined with ===/---) |
| Bullet marker | Unordered lists use -, *, or + |
| Code blocks | Fenced (```) or indented (4 spaces) |
| Keep raw HTML | Elements with no Markdown equivalent (div, span, iframe, video…) stay as HTML inside the Markdown instead of being unwrapped |
| Clean HTML | Before converting, strips script/style/meta elements and class/id/style/data-*/on*/aria-* attributes — pasted web pages produce tidy Markdown |
Options are saved in your browser and applied immediately: changing one re-converts the HTML pane on the spot.
The preview renders the HTML pane as a readable document — headings, tables, code blocks, blockquotes, images. It is sanitized with DOMPurify, so scripts or event handlers in pasted HTML never execute. The preview updates live along with the conversion.
| Shortcut | Action |
|---|---|
Ctrl+O | Open a file |
Ctrl+S | Save the focused pane (Markdown if neither pane has focus) |
Ctrl+Shift+C | Copy the focused pane to the clipboard |
Ctrl+E | Toggle the rendered preview |
Ctrl+Z / Ctrl+Y | Undo / redo inside an editor pane |
Cmd instead of Ctrl.
Both panes are saved to localStorage after every conversion. When you return to the page,
your last session is restored automatically. 🗑 Clear empties the panes and the autosave.
The Dual HTML & MD Editor processes everything locally in your browser.
No data is transmitted to any server — not the files you open, not the content you type.
All persistent state (your two panes and your options) is stored in localStorage
and never leaves your device. The conversion libraries are loaded from public CDNs on first visit,
which is the only network access the page makes.
.html · .htm · .md · .markdown · .txt
Technologies used:
Built with: