Markdown-it is a high-speed Markdown parser with 100% CommonMark support, extensions & syntax plugins.
Cost / License
- Free
- Open Source (MIT)
Platforms
- Self-Hosted

Apps similar to ShowdownJS include Markdown-it, which is free and open source. Other options are Markdeep, Snarkdown, Strapdown.js and Marked.js. In total there are six apps like ShowdownJS for self-hosting.
Markdown-it is a high-speed Markdown parser with 100% CommonMark support, extensions & syntax plugins.

Markdeep is an encompassing JavaScript library for rendering Markdown in the browser. It requires no dependencies and directly supports advanced features like charts and diagrams, fenced code blocks, schedule lists and much more.

Create Markdown documents using JavaScript and Bootstrap themes. Strapdown.js makes it embarrassingly simple to create elegant Markdown documents. No server-side compilation required. Use it to quickly document your projects, create tutorials, home pages, etc.