Markdown
Markdown H1 Checker
Check a document has exactly one top-level H1.
How it works
- 1Paste your Markdown.
- 2The checker reports how many H1s it found.
- 3Fix the document to have exactly one.
Use cases
- Validate a page before publishing.
- Enforce SEO heading rules.
- Catch accidental extra H1s.
Frequently asked questions
Why have only one H1?
A single H1 is best for SEO and screen readers — it states the page’s main topic once.
What does it report?
A pass for exactly one H1, or a list of the H1s when there are zero or several.
Is it private?
Yes. Everything runs in your browser — nothing is uploaded.
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