markedjs/marked

Marked is a fast, lightweight JavaScript library that converts Markdown text into HTML. Markdown is a plain-text writing format where you use simple symbols, like # for headings, ** for bold, or - for bullet lists, and Marked's job is to parse that text and produce the equivalent HTML code that browsers can render. The problem it solves is the universal need to turn human-readable text formatting into web-ready HTML without writing a full parser from scratch. The library is built as a low-level compiler, meaning it processes Markdown line by line without building an intermediate syntax tree that needs to be held in memory, which keeps it fast and memory-efficient. It supports the most common Markdown flavors: the original Markdown specification, CommonMark (a standardized, unambiguous version), and GitHub Flavored Markdown (GFM), which adds features like strikethrough, tables, and task lists. The library is extensible, you can plug in custom tokenizers and renderers to handle your own syntax rules. One important note: Marked does not sanitize the HTML it produces, so if the Markdown source comes from untrusted users, you need to run the output through a separate sanitization library like DOMPurify before injecting it into a web page. You would use Marked when building a blog, documentation site, comment system, or any application where users write in Markdown and you need to display it as HTML. It works in the browser (loaded via a script tag or ES module), as a Node.js library in a server-side application, or as a command-line tool for batch converting Markdown files. The tech stack is pure JavaScript with no runtime dependencies, distributed as an npm package under the MIT license.