Markdown Previewer
Type Markdown on the left and watch a clean, live HTML preview render on the right — then copy the HTML, view the source, or download it as a file, all in your browser.
Markdown Previewer
Type Markdown on the left and watch the live HTML preview update on the right.
Features
- Headings, bold, italic, and
inline code - Ordered and unordered lists
- Links and blockquotes
Everything runs locally in your browser.
function hello(name) {
return 'Hi, ' + name + '!'
}
| Tool | Type |
|---|---|
| Markdown Previewer | Dev |
- Write Markdown
- Copy the HTML
- Ship it
Your Markdown is rendered locally in your browser — nothing is uploaded to any server.
Understanding the Markdown Previewer
Markdown Previewer is a free, client-side tool for writing Markdown and seeing the rendered HTML instantly. Type in the left pane and a clean, styled preview appears on the right, updating on every keystroke. It is built for developers, technical writers, README authors, and anyone drafting documentation, GitHub issues, or blog posts who wants to check formatting before publishing. You can copy the generated HTML, inspect the raw HTML source, or download it as a standalone .html file. Everything runs locally in your browser using the marked library — your text is never uploaded to a server, so even sensitive notes stay private on your machine.
How it works
As you type, your Markdown string is passed to the marked parser with GitHub Flavored Markdown (GFM) enabled. Marked tokenizes the text — detecting headings (#), emphasis (* or _), lists, links, blockquotes (>), fenced code blocks (```), and pipe tables — then walks those tokens and emits matching HTML elements. The result is a synchronous HTML string that React injects into the preview pane, where scoped CSS styles the headings, code, tables, and quotes. The conversion is memoized so it only re-runs when your input changes. Copy actions use the Clipboard API, and the download builds a Blob and a temporary link. No network requests are made at any point.
Worked example
Type `## Setup` followed by a blank line and `1. Install deps` then `2. Run "npm start"`. The preview instantly shows a bold sub-heading and a numbered list with two items. Add a fenced block — three backticks, `const x = 1`, three backticks — and it renders as a dark code box with monospace text. Click "View HTML source" and you'll see exactly `<h2>Setup</h2>`, an `<ol>` with two `<li>` items, and a `<pre><code>` block. Hit "Copy HTML" to paste that markup straight into an email or CMS.
Tips & common mistakes
- Use a blank line between block elements — a list or heading glued to the line above may not render as expected in CommonMark.
- For tables, every row needs matching pipe (|) columns plus the header separator row (|---|---|), or marked treats it as plain text.
- Fence code blocks with three backticks on their own lines; an unclosed fence will swallow everything after it as code.
- Indent nested list items by two spaces (or a tab) under their parent to get proper sub-lists.
- Use "View HTML source" to grab clean markup for a CMS, then "Copy HTML" — handy when an editor strips Markdown but accepts HTML.
- This is a preview tool: the HTML is rendered as-is without sanitization, so only paste Markdown you trust if you later reuse the output on a live site.
Related tools
Frequently Asked Questions
Which Markdown flavor does it support?
It uses the marked library with GitHub Flavored Markdown (GFM) enabled, so on top of CommonMark you get tables, fenced code blocks, and autolinks.
Can I get the HTML out?
Yes. Click “Copy HTML” to copy the generated markup, toggle “View HTML source” to inspect it, or download it as a standalone .html file.
Does it render live as I type?
Yes. The preview re-renders instantly on every keystroke — there is no button to press and nothing is sent to a server.