markdown v1.0
A single-page Markdown editor with live preview. No dependencies, no build step. Write Markdown and see it rendered in real time — all in your browser.
Features
- Live PreviewRendered HTML updates as you type with a smooth 150ms debounce.
- Resizable PanesDrag the divider or toggle panes individually to suit your workflow.
- Copy HTMLCopy the rendered output to your clipboard with one click.
- Save .mdDownload your work as a Markdown file.
- Synced ScrollKeep the editor and preview scrolled to the same position.
- Light & Dark ModeFollows your system preference with manual override and cross-tab sync.
- Keyboard AccessibleSkip link, full keyboard navigation, and screen reader support.
Quick Start
Open index.html in any modern browser. Paste or type Markdown into the left pane and watch it render on the right. Use the toolbar to copy the HTML, save the file, clear the editor, or toggle panes.
Tip: The tab key inserts two spaces for indentation. Use the divider between panes to adjust the split ratio, or use arrow keys when the divider is focused.
Keyboard Shortcuts
Ctrl+1 Toggle editor pane
Ctrl+2 Toggle preview pane
Ctrl+3 Toggle synced scroll
Ctrl+Shift+C Copy HTML
Ctrl+S Save .md
Tab Insert 2 spaces
← → Resize panes
Technical Details
- Framework: Vanilla JavaScript (ES5-compatible), no dependencies
- Rendering: marked.js bundled locally for offline use
- Format: CommonMark and GitHub Flavored Markdown (GFM)
- Theme: Free Open Tools ecosystem dark/light scheme with no-flash detection
- Accessibility: Skip link, keyboard navigation,
aria-liveannouncements, reduced-motion support - Offline: Fully functional with no network — all assets bundled locally
Version History
1.0current
- Initial public release
- Live Markdown preview with 150ms debounce
- Resizable split panes with keyboard support
- Copy rendered HTML to clipboard
- Save work as .md file
- Synced scrolling between editor and preview
- Confirmation dialog before clearing content
- Light and dark mode with system preference detection
- Fully keyboard accessible with skip link and screen reader support
- Free Open Tools ecosystem design tokens and toolbar