What is GitHub-flavored Markdown (GFM)?

GitHub-flavored Markdown is an extension of standard Markdown maintained by GitHub. It adds support for tables, task lists (checkboxes), strikethrough text, autolinked URLs, and fenced code blocks with language-specific syntax highlighting. GFM is the de facto standard for README files, issues, and pull requests on GitHub.

Does the previewer support syntax highlighting in code blocks?

Yes. Fenced code blocks with a language identifier (e.g. ```javascript) are automatically syntax-highlighted using highlight.js via the rehype-highlight plugin. Over 190 languages are supported, including JavaScript, TypeScript, Python, Go, Rust, SQL, and more.

Can I use raw HTML inside my Markdown?

Yes. The previewer uses the rehype-raw plugin, which means inline HTML tags like , , , and are rendered as expected. This is useful for elements that Markdown syntax alone cannot express, such as collapsible sections or keyboard shortcuts.

How does the Export HTML feature work?

Clicking 'Export HTML' downloads a self-contained .html file that includes the rendered Markdown wrapped in a minimal, responsive stylesheet. The file can be opened in any browser, shared via email, or hosted on a static server without additional dependencies.

Is my Markdown content sent to a server?

No. All rendering happens entirely in your browser using client-side JavaScript. Your content never leaves your device — there are no API calls, no analytics on input, and no server-side processing. This makes the tool safe for previewing sensitive documentation or private notes.

What is the difference between Copy HTML and Export HTML?

Copy HTML copies the raw inner HTML of the rendered preview to your clipboard, which you can paste into an email client, CMS, or HTML file. Export HTML downloads a complete standalone HTML page with embedded styles, ready to open in a browser or deploy.

Free Markdown Previewer Online – Live preview

Features

Bold, italic, and ~~strikethrough~~

Links and images

Code blocks with syntax highlighting

Code Example

function greet(name) { return `Hello, ${name}!`; } console.log(greet("world"));

Inline code: const x = 42;

Table

Feature	Supported
Tables	✅
Task lists	✅
Strikethrough	✅
Code highlight	✅
Raw HTML	✅

Feature

Supported

Tables

✅

Task lists

✅

Strikethrough

✅

Code highlight

✅

Raw HTML

✅

Task List

Write Markdown

Preview in real time

Export to HTML

Blockquote

Markdown is a lightweight markup language for creating formatted text using a plain-text editor.

That's it — start editing on the left!

Markdown Previewer — Render GitHub-Flavored Markdown in Real Time

Markdown is the dominant lightweight markup language for software documentation, technical writing, and web content. Created by John Gruber in 2004, it lets authors write plain text that converts cleanly to HTML without the overhead of a WYSIWYG editor. Today, Markdown powers README files on GitHub and GitLab, documentation sites built with tools like Docusaurus and MkDocs, static site generators such as Hugo and Jekyll, note-taking apps like Obsidian and Notion, and virtually every developer platform that accepts user-generated content.

GitHub-flavored Markdown (GFM) extends the original CommonMark specification with features that developers rely on daily. Tables let you present structured data without switching to HTML. Task lists provide interactive checkboxes for tracking progress in issues and pull requests. Strikethrough text marks obsolete information clearly. Autolinked URLs remove the friction of wrapping every link in angle brackets. Fenced code blocks with language identifiers enable syntax highlighting that makes code snippets readable at a glance. These extensions are formalized in the GFM specification maintained by GitHub and implemented by the remark-gfm plugin used in this tool.

Why Use an Online Markdown Previewer?

While many code editors offer built-in Markdown preview, a dedicated online previewer fills several gaps. It provides instant feedback without installing an editor, making it ideal for quick README drafts, issue descriptions, or documentation snippets. It renders the same GFM syntax that GitHub uses, so what you see in the preview matches what will appear on your repository. It works on any device with a browser — including tablets and phones where a full IDE is impractical. And because this tool runs entirely in the browser with no server round-trips, your content stays private and latency is zero.

Syntax Highlighting for Code Blocks

Code blocks are a core part of technical documentation. This previewer uses the rehype-highlight plugin, which integrates highlight.js to tokenize and colorize code in over 190 languages. Simply specify the language after the opening triple backticks — for example, ```typescript — and the renderer applies accurate, theme-aware highlighting. Supported languages include JavaScript, TypeScript, Python, Go, Rust, Java, C, C++, Ruby, PHP, SQL, Bash, YAML, JSON, HTML, CSS, and many more. Highlight.js detects language grammars at build time, so there is no runtime overhead for unused languages.

Raw HTML Support

Standard Markdown intentionally limits its feature set to keep the syntax simple. When you need elements that Markdown cannot express — collapsible sections with <details> and <summary>, keyboard shortcut badges with <kbd>, highlighted text with <mark>, or custom <div> wrappers with class attributes — you can embed raw HTML directly. The rehype-raw plugin parses and renders these elements faithfully, giving you full control when Markdown syntax falls short.

Exporting to HTML

The Export HTML feature generates a standalone HTML document that includes a minimal, responsive stylesheet. The exported file is fully self-contained: it loads no external scripts, stylesheets, or fonts. This makes it suitable for embedding in email campaigns where external resources are blocked, hosting on static file servers, converting to PDF using a headless browser, or archiving documentation offline. The Copy HTML button provides the raw inner HTML without the wrapper document, useful for pasting into content management systems, email templates, or custom web pages where you already control the surrounding markup.

Privacy and Performance

Every keystroke is processed entirely in your browser. The Markdown source is parsed by remark, transformed through rehype plugins, and rendered to the DOM without any network requests. There is no backend, no database, and no telemetry on your input. This architecture delivers sub-millisecond rendering for typical documents and guarantees that sensitive content — internal documentation, credentials, API keys pasted accidentally — never leaves your machine.