What it means
The heading hierarchy on the page does not describe its structure. In practice that is one of four things: no H1 at all, several H1s, levels skipped on the way down (H2 straight to H4), or heading tags chosen because of how large they render rather than what they contain.
Why it matters
Screen-reader users navigate by heading — jumping between them is the fastest way to scan a page, and a broken outline makes that navigation useless. Search engines use the same outline to work out what a page is about and which parts of it answer which query. And a page whose headings are chosen by font size usually has a content problem underneath the markup problem: nobody decided what the page’s sections were.
How W3Audit detects it
The heading outline of every audited page is extracted and evaluated as a tree: H1 count, skipped levels, empty headings, headings containing only an image or icon, and text styled to look like a heading while being marked up as a paragraph. Because outlines are usually produced by a shared template, identical outlines are reported once with the affected URLs listed.
How severe it is
Medium on a single page. High when a template is at fault and the outline is broken across a section, or when a page has no H1 at all — that one has an SEO cost as well as a navigation cost. Multiple H1s are medium in modern practice: search engines cope, screen-reader users are the ones who suffer.
How to fix it
One H1 per page, describing the page. Then descend in order, and let CSS handle size.
<!-- broken: level skipped, size-driven markup -->
<h1>Website Audit</h1>
<h4>What we check</h4>
<p class="looks-like-a-heading">Performance</p>
<!-- correct: outline matches structure -->
<h1>Website Audit</h1>
<h2>What we check</h2>
<h3>Performance</h3>
<h3>Accessibility</h3>
<h2>How findings are ranked</h2>
Never use a heading element for a subtitle or an eyebrow label — those are paragraphs with a class. And do not skip a level to get a smaller size: add a class instead.
How to verify the fix
Extract the outline with an accessibility inspector or heading-map tool and read it on its own. It should read like a sensible table of contents with no gaps in level. Then navigate the page by heading with a screen reader — if you can reach every major section that way and nothing surprising is announced, the structure is correct.
Where this sits in your audit
This finding belongs to the SEO & content category — see the SEO & content audit for everything else reviewed alongside it, or the methodology for how its severity and score contribution are calculated. The website audit checklist includes it as a step you can run yourself.