Markdown Preview

How to Use the Markdown Previewer

1. Type or paste Markdown into the editor pane on the left (or top on mobile).
2. See the live preview — rendered HTML appears on the right as you type with 150ms debounce.
3. Switch output modes — choose Preview for rendered HTML, Raw HTML for the generated source code, or Side-by-Side for a compact view.
4. Copy or download — use the buttons above the output to copy the result to your clipboard or download it as an .html or .md file.

What This Tool Does

This Markdown previewer converts your Markdown text into rendered HTML entirely in your browser. It uses a custom parser built from scratch with no external dependencies, handling the complete CommonMark specification plus popular extensions like tables, strikethrough, and fenced code blocks. The parser works in two phases: first it identifies block-level structures such as headings, code blocks, lists, and blockquotes, then it processes inline formatting within each block, including bold, italic, links, images, and inline code.

Features

• Live preview — Markdown renders as you type with real-time updates and a 150ms debounce for smooth performance
• Full syntax support — headings, bold, italic, strikethrough, inline code, fenced code blocks, links, images, lists, blockquotes, horizontal rules, and tables
• Three output modes — rendered preview, raw HTML source, or side-by-side comparison
• No external dependencies — the Markdown parser is built entirely from scratch, meaning zero network requests and no CDN failures
• Privacy — your Markdown never leaves your browser, nothing is sent to any server
• Download options — save the rendered HTML or the raw Markdown file to your machine

Supported Markdown Syntax

The parser handles all standard Markdown elements. Headings are created with one to six # symbols. Bold text uses double asterisks **bold** or double underscores __bold__. Italic text uses single asterisks *italic* or single underscores _italic_. You can combine them for bold italic with triple asterisks ***text***. Strikethrough uses double tildes ~~deleted~~. Inline code is wrapped in backticks, and fenced code blocks use triple backticks with an optional language identifier for syntax class names.

Tables

Markdown tables are supported with the pipe-based syntax. Create columns separated by | characters, with a separator row of dashes indicating the header boundary. You can align columns left, center, or right using colons in the separator row: :--- for left, :---: for center, and ---: for right alignment. Tables are rendered as full HTML tables with proper th and td elements.

Code Blocks

Fenced code blocks wrap your code in <pre><code> elements. When you specify a language after the opening backticks (for example, ```javascript), the code element receives a language-* class that is compatible with popular syntax highlighting libraries like Prism.js and highlight.js. The parser correctly handles code that contains special HTML characters, escaping them so they display literally rather than being interpreted as HTML.

Lists and Blockquotes

Unordered lists use - or * as bullet markers, and ordered lists use numbers followed by a period. The parser correctly handles multi-level nesting based on indentation. Blockquotes are created with the > character at the start of a line and can contain any other Markdown elements inside them. Multiple levels of blockquotes are supported by stacking > characters.

Use Cases for Markdown Preview

Developers use Markdown preview tools to draft README files before pushing them to GitHub, to write documentation for open-source projects, to preview blog posts for static site generators like Jekyll or Hugo, and to test formatting before pasting into issue trackers, pull request descriptions, or wikis. Technical writers use it to verify that their documentation renders correctly across platforms. Students use it to format notes and assignments. Anyone who writes Markdown regularly benefits from a fast, private preview tool that does not require installing software or creating accounts. Need to convert between HTML and Markdown? Use our HTML/Markdown Converter. To compare different versions of your document, try the Diff Checker, or count words and reading time with the Word Counter.