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Heading hierarchy validator.
Outline + SEO + a11y flags.

Paste a page's HTML (or markdown # headings) — we render the H1..H6 outline and flag missing H1, multiple H1s, skipped levels (H1 → H3), empty headings, and deep nesting. The same checks Google's SEO docs + screen-reader tools care about. Pure client-side.

HTML or markdown
HTML mode: we parse <h1>...<h6> tags with their attributes and inline children stripped. Markdown mode: if no HTML headings exist, we look for # ATX-style headings.
Outline (9 headings)
  • H1Why LLMs cite some sites and not others
  • H2The shift from search to answers
  • H2What gets quoted
  • H3Structure
  • H3Source authority
  • H4Citations from .edu / .gov
  • H2What you can do today
  • H3Add structured data
  • H3Write quotable sentences
H1
1
H2
3
H3
4
H4
1
H5
0
H6
0
Clean outline — no issues.

    Vyrable's content engine writes posts with proper heading structure by default — H1 for the title, H2 for sections, H3 for sub-points, no skipped levels.