Markdown Preview

Client-Side

Write and preview Markdown with live rendering. No data leaves your browser.

791 chars · 130 words
Markdown
Preview

Welcome to Markdown Preview

This is a live preview tool that renders your Markdown in real time.

Features

  • Bold and italic text
  • Inline code and code blocks
  • Links and images
  • Tables, lists, and blockquotes

Code Block

function greet(name) {
  return `Hello, ${name}!`;
}

console.log(greet("World"));
Markdown is a lightweight markup language that you can use to add
formatting elements to plaintext text documents.

Table Example

FeatureSupported
HeadingsYes
Bold/ItalicYes
Code blocksYes
TablesYes
ListsYes

Ordered List

  1. First item
  2. Second item
  3. Third item

Built with zero dependencies. No data leaves your browser.

About This Tool

Writing Markdown without seeing the rendered output makes it hard to catch broken links, mismatched code fences, or formatting mistakes until they show up live.

This previewer takes Markdown on the left and renders HTML on the right in real time as you type. It supports the standard CommonMark spec plus GitHub Flavored Markdown extensions (tables, task lists, autolinks, fenced code blocks, strikethrough). Code blocks get syntax highlighting for common languages. Math is supported via LaTeX-style $...$ and $$...$$ blocks if you toggle that on.

The preview updates in real time as you type, which makes it a useful scratchpad for drafting blog posts, READMEs, or documentation. Output can be copied as HTML or as the original Markdown — useful when pasting into apps that accept either format. No data is sent anywhere; the rendering happens entirely in your browser.

The rendering pipeline is two stages: parse Markdown to a syntax tree, then walk the tree emitting HTML. The parser implements CommonMark — the de-facto Markdown standard with consistent rules across implementations — plus GitHub Flavored Markdown extensions. Tables, task lists ([ ] and [x]), strikethrough (~~text~~), autolinks (URLs without brackets), and fenced code blocks all work. Code syntax highlighting uses a lightweight library that handles the major languages. Math rendering uses KaTeX, which is fast (faster than MathJax) and supports most common LaTeX math syntax.

The pain this addresses: writing Markdown without seeing the output produces formatting bugs that show up only after publishing. Mismatched code fences turn the rest of your document into one giant code block. Wrong heading levels disrupt the document outline. Broken link syntax shows literal brackets in the rendered page. The preview shows these as you type, so the feedback loop is short — you fix issues immediately rather than discovering them after pushing to production.

Worked example: type '# Hello\n\n**bold** and *italic* and `code`.\n\n[link](https://example.com)\n\n```python\nprint("hello")\n```'. The preview renders this as a heading, a paragraph with formatting, a clickable link, and a syntax-highlighted code block. The Markdown source stays editable; the preview updates per keystroke. Copy the rendered HTML directly to paste into a CMS that wants HTML rather than Markdown. Or copy the original Markdown to commit to a repo that prefers source format.

Where Markdown gets weird: tables. The pipe syntax (| col1 | col2 |) is verbose to type and visually messy. Tools like the Markdown table generator (which is a separate task) produce them faster. Footnotes are extension territory — supported here but inconsistent across renderers. Reference-style links (using [name][ref] with the URL defined elsewhere) work but are less common than inline. The preview supports all of these with reasonable behavior, but if your output is being consumed by a tool that doesn't support GFM extensions, restrict yourself to vanilla CommonMark to maximize portability.

The about text and FAQ on this page were drafted with AI assistance and reviewed by a member of the Coherence Daddy team before publishing. See our Content Policy for editorial standards.

Frequently Asked Questions

Which flavor of Markdown is this?
CommonMark with GitHub Flavored Markdown extensions. Tables, task lists, autolinks, strikethrough, and fenced code blocks all work. Reference-style links and footnotes are supported. Some niche dialects (MultiMarkdown, Pandoc's extensions) are not.
Does math notation work?
Yes — toggle math support, then use single dollar signs for inline ($x^2$) or double dollar signs for display blocks. Rendered with KaTeX, which is fast and supports most LaTeX math syntax. Some advanced LaTeX packages aren't available.
Can I export as HTML?
Yes — copy the HTML directly from the preview pane, or use the export button to download as a standalone HTML file with embedded styles. Useful for emailing rich text to people who can't read Markdown.
Does it support custom CSS?
There's a styling option with a few preset themes (GitHub, classic, minimal). Custom CSS isn't supported in the lightweight version. For full control, copy the HTML and apply your own stylesheet downstream.
What about syntax highlighting?
Yes — common languages (JavaScript, Python, Ruby, Go, Rust, SQL, Bash, etc.) get syntax highlighting in fenced code blocks. Specify the language after the opening fence: ```python. Without a language specifier, code is displayed in monospace without highlighting.
Does it support diagrams?
Mermaid diagrams (flowcharts, sequence, gantt) work if you toggle the extension. The syntax is fenced code blocks tagged with 'mermaid'. Useful for documentation and READMEs that need flowcharts inline. Not all Markdown renderers support Mermaid — GitHub does, most static site generators do, generic CommonMark doesn't.
How does this differ from a static site generator?
Generators (Hugo, Jekyll, Astro) build complete websites from Markdown sources, with templates, navigation, and asset pipelines. The previewer just renders one file at a time. Use the previewer for drafting; use a generator for publishing. Many writers compose in the previewer, then commit to a repo where a generator builds the live site.