markdown-it

library14.1.1jsnpmunverified

Markdown-it is a high-performance and highly extensible Markdown parser, currently at version 14.1.1. It strictly follows the CommonMark specification while also offering several useful syntax extensions like URL autolinking, smart typography (typographer), and HTML tag support. Known for its speed and configurability, users can easily add, modify, or replace parsing rules and extend functionality via a rich ecosystem of community-developed plugins available on npm. It prioritizes safety by design and is suitable for both Node.js and browser environments. The project maintains an active development pace with frequent updates, ensuring ongoing compatibility and feature enhancements.

serialization

npm install markdown-it

github ↗package ↗

INSTALL

IMPORT

SIG · MARKDOWN-IT

markdown-it

serializationjavascriptv14.1.1

Install

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Import

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Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

markdownit

✓ import markdownit from 'markdown-it'

✗ import { markdownit } from 'markdown-it'

Primary ESM import for Node.js and modern browser bundlers. It's a default export.

markdownit

✓ const markdownit = require('markdown-it')

CommonJS import for Node.js environments. This is the traditional way for older projects.

MarkdownIt

✓ import type MarkdownIt from 'markdown-it'

For TypeScript users to import the type definition of the default export.

window.markdownit

✓ const md = window.markdownit()

For browser environments loading markdown-it via a <script> tag (UMD build). Note the global is `markdownit` (no dash).

Demonstrates basic markdown-it initialization with common options, renders a block of Markdown text, and shows inline rendering for single-line content.

import markdownit from 'markdown-it'; // Initialize markdown-it with specific options const md = markdownit({ html: true, // Enable HTML tags in source linkify: true, // Autoconvert URL-like text to links typographer: true // Enable smart quotes and other typographic replacements }); // Example 1: Basic rendering const markdownText1 = '# Hello, markdown-it!\n\nThis is a *simple* paragraph with an [example link](https://example.com).'; const htmlResult1 = md.render(markdownText1); console.log('Basic Render:\n', htmlResult1); // Example 2: Render inline content (without paragraph wrap) const markdownText2 = '__markdown-it__ rulezz!'; const htmlResult2 = md.renderInline(markdownText2); console.log('\nInline Render:\n', htmlResult2); // Example 3: Demonstrating typographer and linkify const markdownText3 = 'Check out google.com or write "hello" here.'; const htmlResult3 = md.render(markdownText3); console.log('\nTypographer & Linkify:\n', htmlResult3);

Debug

Known issues

gotchaWhen using markdown-it in a browser environment via a `<script>` tag, the global variable created is `window.markdownit` (without a hyphen). Attempting to access `window.markdown-it` will result in a `ReferenceError`.

fix

Access the global instance using `window.markdownit`.

affects: >=1.0.0

breakingEarlier versions of markdown-it (prior to v11) had a different default preset. If you are upgrading from a very old version, some default rules or options may have changed, potentially altering rendering output.

fix

Explicitly initialize with a preset (e.g., `markdownit('default')`) or configure options to match previous behavior after consulting the changelog for your specific upgrade path.

affects: <11.0.0

gotchaWhile markdown-it is designed to be safe by default, using third-party plugins can introduce security vulnerabilities if they are not properly audited. Always review plugin code for potential XSS or other injection risks, especially if processing untrusted user input.

fix

Only use well-vetted and trusted plugins from reliable sources. When in doubt, audit plugin code or sanitize the output further if it contains user-generated content after parsing.

affects: >=1.0.0

gotchaManaging rule priorities and order when adding or replacing custom parsing rules can be complex. Incorrect rule configuration can lead to unexpected parsing behavior or conflicts between rules.

fix

Thoroughly test custom rule sets with diverse Markdown inputs. Consult the 'Development info' documentation on the GitHub repository for guidance on rule management and plugin development.

affects: >=1.0.0

Errors

Common errors & fixes

TypeError: markdownit is not a constructor

Attempting to `import { markdownit } from 'markdown-it'` (named import) instead of `import markdownit from 'markdown-it'` (default import) in an ESM environment, or mixing CJS `require` with an ESM-only context.

fix

Use `import markdownit from 'markdown-it'` for ESM or `const markdownit = require('markdown-it')` for CommonJS.

ReferenceError: markdownit is not defined

In a browser environment, the `markdown-it` UMD build exposes its API on `window.markdownit`. Directly using `markdownit()` without `window.` will result in this error.

fix

Ensure you are referencing `window.markdownit()` when using the UMD build directly in the browser.

My custom plugin isn't working or is conflicting with existing rules.

Incorrectly registered the plugin, specified a wrong rule name, or set an incorrect rule priority, leading to it not firing or being overridden.

fix

Verify plugin registration (`md.use(plugin)`). Check rule names for typos. Adjust rule insertion methods (`.before()`, `.after()`, `.at()`) and priorities to ensure correct execution order.

Upgrade

Version history

14.1.1latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

2 hits · last 30 days

node

Resources

githubhttps://github.com/markdown-it/markdown-it ↗

packagehttps://www.npmjs.com/package/markdown-it ↗