markdown-regex

A set of ready-to-use RegExp constants for parsing and extracting elements from Markdown content.

v2.0 (beta) — Fully rewritten in TypeScript, powered by tsup. Zero runtime dependencies.

Features

• 17+ regex patterns covering common Markdown elements
• Platform-agnostic newlines (works with \n, \r\n and \r)
• Zero runtime dependencies
• First-class TypeScript support (generated .d.ts)
• Dual package: ESM + CommonJS + browser (IIFE)
• Lightweight
• Ready for custom-tag addons

Installation

npm install markdown-regex
# or
yarn add markdown-regex
# or
pnpm add markdown-regex

Quick Start

ESM

import { REGEXP_HEADER, REGEXP_LINK, REGEXP_STRONG, REGEXP_ITALIC } from 'markdown-regex';

const md = `# Title\n\nVisit [GitHub](https://github.com) and **bold** and *italic*.`;
console.log(md.match(REGEXP_LINK));

CommonJS

const { REGEXP_HEADER, REGEXP_LINK } = require('markdown-regex');

Browser (IIFE)

<script src="https://unpkg.com/markdown-regex/dist/index.global.js"></script>
<script>
  const { REGEXP_LINK } = MarkdownRegex;
</script>

API Reference

Export	Description	Matches
REGEXP_HEADER	Markdown headers	# H1, ## H2, …
REGEXP_H2	Level-2 headers	## …
REGEXP_H3	Level-3 headers	### …
REGEXP_IMAGE	Image syntax	
REGEXP_LINK	Link syntax	[text](url)
REGEXP_STRONG	Bold	**bold**, __bold__
REGEXP_ITALIC	Italic	*italic*, _italic_
REGEXP_DEL	Strikethrough	~~deleted~~
REGEXP_CODE	Inline code	`code`
REGEXP_Q	Custom quote	:"quoted":
REGEXP_BLOCKQUOTE	Blockquotes	> quote
REGEXP_HR	Horizontal rules	----- (5+ dashes)
REGEXP_PARAGRAPH	Paragraphs	text between newlines
REGEXP_BR	Line breaks	2+ consecutive newlines
REGEXP_EMPTY_BLOCKQUOTE	Cleanup	</blockquote><blockquote>
REGEXP_UL_LIST	Unordered lists	* item
REGEXP_OL_LIST	Ordered lists	1. item
REGEXP_EMPTY_UL	Cleanup	</ul><ul>
REGEXP_EMPTY_OL	Cleanup	</ol><ol>

Development

npm install
npm run build        # tsup → dist/
npm run typecheck    # tsc --noEmit
npm test             # Jest
npm run dev          # watch mode

Future: Custom Tag Addons

The library is structured so that additional custom regexes can be added under src/addons/ (or published as a separate entry) without touching the core.

Related

• NPM: https://www.npmjs.com/package/markdown-regex
• Used by: https://github.com/LLazyEmail/markdown-to-email
• Article: https://hackernoon.com/open-sourcing-regular-expressions-for-markdown-syntax-module

License

MIT