---
author: Julian Knight (Totally Information)
created: 2026-01-01 21:35:51
updated: 2026-06-02 13:52:43
status: complete
tags: 
  - markdown
  - tests
  - formatting
title: Markdown Formatting Supported by Markweb
shortTitle: Formatting Checks
description: Markweb supports various Markdown features and formatting options.
---

UIBUILDER for Node-RED's `markweb` feature supports a wide range of Markdown formatting options, including Commonmark and some GitHub Flavored Markdown (GFM) extensions.

The basic features are provided by an embedded version of the MarkdownIT and highlight.js libraries, with some custom extensions added for additional formatting and features.

In addition, a number of custom extensions are included to allow for additional formatting and features, such as custom element ID's, classes and attributes, and special processing directives.

Most of the rendering of Markdown to HTML is done on the server, not in the browser. This allows for more powerful processing and features, and also allows for the use of server-side variables and directives in markdown files.

The following pages provide details and examples of the various Markdown features and formatting options supported by Markweb. These are not intended to be a comprehensive guide to Markdown, but rather a reference for the specific features and formatting options supported in Markweb markdown files.

%%index [title="Markdown Formatting Supported by Markweb", id=md-tests-index]%%