This free online Markdown editor runs entirely in your browser. Write and preview Markdown side by side with no installation, no account, and no server uploads. It supports GitHub Flavored Markdown, KaTeX math, Mermaid diagrams, code syntax highlighting, find and replace, auto-draft recovery, and direct file save on Chrome and Edge.
Features What this editor can do
Live Split Preview
The editor and rendered preview update in real time. Switch between split, editor-only, and preview-only modes at any time.
Native File Save
On Chrome and Edge, the Save button writes directly back to your original .md file using the File System Access API. Other browsers download the file.
Math Rendering
Inline and block LaTeX math expressions are rendered by KaTeX. Use $...$ for inline and $$...$$ for display-mode equations.
Mermaid Diagrams
Fenced code blocks tagged with "mermaid" render as flowcharts, sequence diagrams, and Gantt charts in the preview.
Syntax Highlighting
Code blocks are highlighted by highlight.js across dozens of languages. The theme adapts automatically between light and dark mode.
Find and Replace
Press Ctrl+F to open the find bar. Navigate matches, replace one at a time, or replace all occurrences across the full document.
Table of Contents
An auto-generated TOC panel lists every heading in the document. Click any entry to jump to that section in the preview.
Auto-Draft Recovery
Unsaved changes are continuously backed up to localStorage. If the page refreshes unexpectedly, your work is restored automatically.
Shortcuts Keyboard shortcuts
Keys
Action
CtrlS
Save file
CtrlF
Open find and replace
CtrlB
Bold selected text
CtrlI
Italicise selected text
CtrlK
Insert hyperlink
Enter
Continue list on new line
Esc
Close find bar or dialog
Syntax Markdown quick reference
# Heading 1H1 heading
## Heading 2H2 heading
**bold**Bold text
*italic*Italic text
~~strike~~Strikethrough
`code`Inline code
```langFenced code block
[text](url)Hyperlink
Image
> textBlockquote
- itemBullet list
1. itemNumbered list
- [ ] taskTask list item
---Horizontal rule
$E=mc^2$Inline math (KaTeX)
$$...$$Block math (KaTeX)
FAQ Frequently asked questions
Yes, completely free with no sign-up, no subscription, and no usage limits. The editor is a browser-based tool that requires no installation.
No. Everything runs locally in your browser. Files are either saved back to your device (Chrome/Edge) or downloaded as a .md file. Nothing is sent to any external server.
Yes. The editor uses marked.js with GFM enabled. Tables, task lists, strikethrough, and autolinks all render correctly without any extra configuration.
Not directly from the editor itself, but the status bar at the bottom includes quick links to dedicated PDF and HTML conversion tools where you can paste your Markdown and export.
Unsaved content is automatically backed up to your browser's localStorage as you type. When you reopen the page, the draft is restored. The editor will also warn you before closing if there are unsaved changes.
Wrap inline math in single dollar signs, for example $E = mc^2$, and put block-level equations on their own line between double dollar signs. KaTeX renders the output automatically in the preview pane.
Yes. On small screens the interface switches to a single-pane layout with Edit and Read toggle buttons at the top. The formatting toolbar and file operations all remain accessible.
