Check a page’s heading outline for missing h1, skipped levels and empty headings.
View source and paste the body, or paste any fragment
Paste some HTML to see its heading outline and any structural problems.
A skipped heading level is an accessibility fault — screen reader users navigate by level, and a jump implies structure that is not there. It is not a ranking penalty, and this tool does not claim otherwise. Nothing here fetches a live page; it analyses only the markup you paste.
A well-structured page
One h1, no skips
<h1>Title</h1><h2>Section</h2>A skipped level
h1 straight to h4
<h1>Title</h1><h4>Detail</h4>Headings used for styling
Empty headings for spacing
<h3></h3>View source and copy the body, or paste a fragment.
Every heading is listed with its level and text, in document order.
Errors first, then warnings, then observations.
A tokeniser that understands comments, raw-text elements and quoted attributes gives the right answer on real pages, where a regex silently miscounts.
A missing h1 is an error. A skipped level is an accessibility warning. Repeated heading text is an observation. None of them is presented as a ranking penalty.
An unclosed heading stops at the next heading instead of swallowing the rest of the document, so a broken page still produces a usable outline.
Paste HTML and see the heading outline a screen reader would navigate. The analyser scans the markup with a real tokeniser rather than a regular expression, so comments, script bodies and angle brackets inside attributes do not corrupt the result. It reports a missing or duplicated h1, empty headings, skipped levels and repeated heading text, and it is careful about severity: a skipped level is a genuine accessibility fault because assistive technology navigates by level, but it is not a ranking penalty and this tool does not claim it is.
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