Developer ToolsCode ValidatorsFree Tool
Markdown Validator
Check Markdown for a couple of common issues: multiple or missing H1 headings, and empty link syntax.
How to Use Markdown Validator
- 1Paste your Markdown text
- 2Click Process
- 3Review the H1 count, empty-link warnings, and document stats
Frequently Asked Questions
Two things: whether your document has exactly one H1 (# Heading) — more or fewer triggers a warning — and any empty link syntax like [text](). It also reports total lines and word count.
No — only the two checks above. It doesn't verify links resolve, validate table syntax, or catch most other Markdown mistakes.
Having exactly one H1 per document is a common best practice for both document structure and SEO — it's a recommendation, not a hard Markdown syntax rule.
No — checks run entirely in your browser.
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