Markdown previewer
Write Markdown, see it rendered, and copy the HTML out.
The Everything Toolbox
A small but complete Markdown renderer, written from scratch.
What it supports
- Headings, lists and blockquotes
inline codeand fenced blocks- Links and images
- Tables and horizontal rules
- Ordered lists work too
- With nested content
Everything runs in your browser.
Nothing is uploaded.
const greeting = 'hello';
console.log(greeting);| Tool | Category |
|---|---|
| QR code | Developer |
| Tip calculator | Finance |
That is the whole demo.
How it works
Markdown was created by John Gruber in 2004 with a simple goal: a plain-text format that reads naturally as-is and converts cleanly to HTML. Its success is why it now underpins README files, documentation sites, chat apps and note-taking tools.
What this renderer covers
Headings, bold, italic, strikethrough, inline and fenced code, links, images, ordered and unordered lists, blockquotes, horizontal rules and pipe tables. That is the intersection of CommonMark and GitHub Flavored Markdown that people actually use day to day.
What it does not
Nested lists, reference-style links, footnotes, task lists and inline HTML are not supported. A full CommonMark implementation is a genuinely large piece of software — the specification runs to hundreds of edge cases — and this is deliberately a preview tool, not a publishing pipeline.
Escaping order matters
The escaping happens before the Markdown patterns are applied, not after. Doing it the other way round would escape the tags the renderer just produced. Getting this backwards is the classic way homegrown Markdown renderers end up with cross-site scripting holes.