Heading Structure (H1–H6) Checker
Paste a page's HTML or Markdown and see its heading outline as a tree, with the problems flagged: missing or multiple H1s, skipped levels, empty headings, and headings that aren't phrased as anything a reader would search.
- Instant·Runs in your browser
- No signup
- Free
Page source or Markdown
Paste HTML or Markdown
You'll see the heading outline as a tree, with duplicate H1s, skipped levels and empty headings flagged.
Next step
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4 steps
How to use it
- 1Paste the page source (HTML) or the Markdown draft.
- 2Read the outline tree — indentation shows nesting.
- 3Fix any issues listed: one H1, no skipped levels, no empties.
- 4Turn key H2s into questions to match how people ask.
FAQ
Frequently asked
One. HTML5 technically allows more, but Google’s guidance and every AI extraction pipeline treat the H1 as the page’s title. Two H1s means a coin toss.
Not directly as a ranking factor, but a jump from H2 to H4 breaks the outline that screen readers and content extractors build, and AI engines use that outline to decide which passage answers what.
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