Markdown Editor
Write Markdown on the left and see the live sanitized preview on the right.
Why Use a Markdown Editor?
Markdown lets you write in plain text and add formatting with simple syntax. A live preview shows how headings, lists, code blocks, and tables will look without leaving the editor.
Developers use it for README files and documentation, while writers use it for drafts that are easy to convert to other formats.
Preview, Diagrams, and Copy Options
The preview is rendered with marked and sanitized with DOMPurify, so unsafe HTML is stripped. Fenced mermaid blocks become SVG diagrams. The HTML Output tab shows the generated markup, and Copy HTML copies it.
Copy Rich Text writes HTML and plain text to the clipboard for supported editors, and Open .md imports a file from your device. Nothing is uploaded; everything is processed in the browser.
Frequently Asked Questions
What is Markdown?
Markdown is a lightweight plain-text format for headings, lists, links, emphasis, code, and tables. It is widely used for README files, documentation, and notes.
How is the preview rendered?
The editor parses Markdown with marked and sanitizes the result with DOMPurify before displaying it, so the rendered preview and the HTML output are cleaned of unsafe markup.
Are Mermaid diagrams supported?
Yes. A fenced code block labeled mermaid is rendered as an SVG diagram in the preview using Mermaid's strict security level, and the diagram is included in the generated HTML and rich-text copy.
Can I paste the result into Confluence, Notion, or Google Docs?
Copy Rich Text places both HTML and plain text on the clipboard when the browser supports it. Editors that accept rich HTML paste the formatting; otherwise the plain-text fallback is used.
Can I open an existing Markdown file?
Yes. Open .md loads a .md, .markdown, or text file from your device into the editor.
Is my content saved?
No. Content lives in the page for your session only. Copy your Markdown before closing or reloading the page.