Markdown Link Checker

Statically check Markdown links for format errors, broken anchors, and undefined references (no network requests)

Key Facts

Category
Developer & Web
Input Types
textarea, select
Output Type
text
Sample Coverage
4
API Ready
Yes

Overview

The Markdown Link Checker is a static analysis tool designed to scan your Markdown documents for formatting errors, broken internal anchors, and undefined reference links without making any external network requests.

When to Use

  • •Before publishing documentation or blog posts to ensure all internal headers and reference links resolve correctly.
  • •When refactoring large Markdown files and you need to verify that anchor links still match the updated headings.
  • •During offline editing sessions where you want to validate link syntax and reference definitions without internet access.

How It Works

  • •Paste your Markdown content into the input area.
  • •Select your preferred check level, choosing between basic validation or strict validation for unused references and duplicate anchors.
  • •Choose the output report format as either plain text or structured JSON.
  • •Run the check to instantly view a detailed report highlighting syntax errors, missing targets, or broken anchors.

Use Cases

Validating README files and project documentation before committing changes to a repository.
Auditing long-form Markdown books or guides to clean up unused reference-style links.
Checking generated Markdown files from static site generators for broken internal cross-references.

Examples

1. Validating Documentation Anchors

Technical Writer
Background
A technical writer is updating a software user guide written in Markdown with numerous internal section links.
Problem
Several headings were renamed, potentially breaking internal links like [Setup Guide](#installation-setup).
How to Use
Paste the Markdown text into the input, select 'Basic' check level, choose 'Text Report', and run the check.
Example Config
Check Level: Basic, Report Format: Text
Outcome
The tool flags the exact line numbers where anchor links point to non-existent headings, allowing quick fixes.

2. Cleaning Up Reference-Style Links

Open Source Maintainer
Background
A maintainer is reviewing a large README file that uses reference-style links at the bottom of the document.
Problem
Over time, edits have left several unused link references and duplicate anchor definitions cluttering the file.
How to Use
Paste the README content, select 'Strict' check level to catch unused references, and choose 'JSON' report format for automated parsing.
Example Config
Check Level: Strict, Report Format: JSON
Outcome
The tool outputs a JSON report listing all unused reference definitions and duplicate anchors, making cleanup straightforward.

Try with Samples

markdown
Markdown Link Extractor Samples
Sample Markdown documents with various link types for testing the Markdown Link Extractor tool
title token markdown,link
markdown
Markdown Samples
Markdown format examples from simple to complex document structures
title token markdown
markdown
Magnet Link Samples
Sample magnet links for BitTorrent/P2P file sharing testing and validation
title token link
markdown
Markdown Slide Deck Samples
Remark/Marp style Markdown slide decks for testing PDF export layouts
title token markdown
markdown

Related Hubs

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FAQ

Does this tool check external HTTP URLs to see if they are online?

No, this tool performs static analysis only and does not make network requests to verify external websites.

What is the difference between basic and strict check levels?

Basic level checks link formats and broken anchors, while strict level also flags unused reference definitions and duplicate anchors.

Can it detect broken internal section links (anchors)?

Yes, it parses headings to verify that internal anchor links like #section-name point to valid headings in the document.

What formats can I export the validation report in?

You can generate the validation report in either plain text format or structured JSON format.

Does my Markdown data get uploaded to a server?

No, the validation is performed entirely in your browser, keeping your document content private and secure.

API Documentation

Request Endpoint

POST /en/api/tools/markdown-link-checker

Request Parameters

Parameter Name Type Required Description
markdownInput textarea Yes -
checkLevel select No -
reportFormat select No -

Response Format

{
  "result": "Processed text content",
  "error": "Error message (optional)",
  "message": "Notification message (optional)",
  "metadata": {
    "key": "value"
  }
}
Text: Text

AI MCP Documentation

Add this tool to your MCP server configuration: 

{
  "mcpServers": {
    "elysiatools-markdown-link-checker": {
      "name": "markdown-link-checker",
      "description": "Statically check Markdown links for format errors, broken anchors, and undefined references (no network requests)",
      "baseUrl": "https://elysiatools.com/mcp/sse?toolId=markdown-link-checker",
      "command": "",
      "args": [],
      "env": {},
      "isActive": true,
      "type": "sse"
    }
  }
}

You can chain multiple tools, e.g.: `https://elysiatools.com/mcp/sse?toolId=png-to-webp,jpg-to-webp,gif-to-webp`, max 20 tools.

If you encounter any issues, please contact us at [email protected]