# Markdown Lint and Style Checker Lint Markdown against ~15 markdownlint rules plus 2 Chinese-typography rules, with line-located reports and one-click auto-fix of safe issues > Canonical page: https://elysiatools.com/en/tools/markdown-lint-style-checker - **Category:** Text Processing - **Keywords:** markdown, lint, markdownlint, style, checker, readme, documentation, prose, chinese typography, cn001, auto fix ## Overview Tokenizes Markdown into blocks and runs a markdownlint-inspired rule engine (MD001/004/009/012/013/022/024/025/029/031/032/040/041/042/045/047) plus Chinese-typography rules (CN001 space between Chinese and Latin/digits). Reports each issue with its line, rule ID, severity, and a fix hint. Auto-fix applies only safe deterministic fixes (trailing whitespace, blank lines, list markers, trailing newline). Three rule sets: Default, Strict, Lenient. ## Inputs - **Markdown Content** (textarea): # Title Some Markdown with issues... - item one * item two (mixed markers) ``` code without language ``` ##使用Python3 (missing space) - **Rule Set** (select) - **Auto-fix safe issues** (checkbox) ## When to use - Before publishing documentation, README files, or blog posts to ensure consistent formatting and style. - When editing mixed-language documents containing both Chinese and English/digits to automatically fix spacing issues. - To quickly clean up messy Markdown files by automatically fixing trailing whitespaces, consecutive blank lines, and missing list markers. ## How it works - Paste your Markdown content into the text area and select your preferred rule set (Default, Strict, or Lenient). - Enable the auto-fix option if you want the tool to automatically resolve safe, deterministic formatting issues. - Review the generated report highlighting specific rule violations, line numbers, severity levels, and suggested fixes. ## Use cases - Standardizing project README files before committing them to version control repositories. - Polishing technical documentation to ensure correct heading hierarchies and code block formatting. - Formatting bilingual Chinese-English articles to automatically insert proper spacing between different character sets. ## Frequently asked questions ### What rules does the Markdown Lint and Style Checker validate? It checks ~15 standard markdownlint rules (like heading levels, list markers, and code fences) and Chinese-typography rules (like spacing between Chinese and Latin characters). ### What issues can the auto-fix feature safely resolve? It automatically fixes trailing whitespaces, consecutive blank lines, inconsistent list markers, missing blank lines around headers/lists, and missing trailing newlines. ### What is the difference between the Default, Strict, and Lenient rule sets? Default checks standard rules; Strict adds strict line length (MD013) and ordered list prefix checks; Lenient suppresses style warnings to focus only on errors. ### Does the tool modify my original Markdown structure or content? No, it only fixes safe formatting issues. Structural issues like skipped heading levels or missing code block languages are reported for manual correction. ### How does the Chinese-typography rule (CN001) work? It detects and flags missing spaces between Chinese characters and Latin characters or digits, helping you maintain clean, readable bilingual text. ## Related tools - [Markdown Link Extractor](https://elysiatools.com/en/tools/markdown-link-extractor): Extract inline links, reference links, and bare URLs from Markdown documents with basic syntax validation - [Indented List to ASCII Tree](https://elysiatools.com/en/tools/ascii-tree-from-indented-list): Convert a 2-space / 4-space / Tab indented hierarchical list (Markdown bullets, -, *, 1. prefixes optional) into a copyable ASCII directory tree. Two styles: Unicode box-drawing (├──└──│) for GitHub/Discord and classic ASCII (|--\--|) for plain text. 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