Heading Structure Checker & Accessibility Outline

What is the Heading Structure Checker?

The Heading Structure Checker extracts native H1-H6 elements and optional role="heading" semantics from pasted HTML, or # through ###### headings from Markdown. It can focus on the main element so site-wide header, navigation, sidebar, and footer headings do not automatically distort the content outline, while an entire-document mode remains available.

The tool reviews logical hierarchy, main-heading usage, descriptive labels, hidden source states, ARIA levels, accessible-name differences, section labels, and anchor IDs. Its source-based screen-reader list is a preview, not a rendered-browser or assistive-technology test: external CSS, JavaScript changes, shadow DOM, responsive variants, and a live accessibility tree are outside its scope.

How to audit a heading structure

1. Paste complete HTML, a main-content fragment, or Markdown. Add the expected topic or a page-title override only when those optional comparisons are useful.
2. Choose Main content when available to separate the article or tool outline from recurring site-wide headings. Choose Entire document when auditing all landmarks together.
3. Keep ARIA headings enabled when legacy markup may use role="heading". Invalid or missing aria-level values are flagged, while native H1-H6 elements remain the preferred default.
4. Review the visual tree and source-based screen-reader list. Fix empty headings, skipped downward levels, invalid ARIA semantics, and duplicate IDs before lower-impact wording or anchor suggestions.
5. Confirm the final report, then copy or download text, Markdown, CSV, or JSON. Continue to GEO Content Checker only when a broader content audit is needed and the source is within the handoff limit.

Benefits of this heading audit

• Audit the main content separately from header, navigation, sidebar, and footer headings when a main element exists.
• See native and ARIA headings in source order with level, accessible name, context, approximate line, ID, hidden state, and issue badges.
• Detect downward level skips without incorrectly treating a return from a deep subsection to a higher-level sibling as an error.
• Find empty headings, duplicate labels, conservative vague labels, very long headings, hidden H1 elements, invalid ARIA levels, accessible-name differences, and duplicate anchor IDs.
• Compare the page title and expected topic with the primary heading without requiring identical wording or claiming that multiple H1 elements are an automatic Google ranking failure.
• Use one live state for the visual outline, screen-reader list preview, score, findings, copy, downloads, and optional GEO Content Checker handoff.

Heading Structure Checker FAQ

Is more than one H1 always an SEO error?

No. Multiple H1 elements are allowed in some HTML situations, but current general guidance favors one descriptive page H1 and logically nested subheadings. The tool marks multiple exposed H1 elements for review rather than claiming an automatic ranking penalty.

Does the H1 have to exactly match the title element?

No. They should independently describe the same page, but exact wording is not required. The optional comparison checks topic overlap and explains the result as a heuristic.

Why are skipped heading levels flagged?

A downward jump such as H2 to H4 can make the hierarchy confusing, especially in heading navigation. Moving from H4 back to H2 is not flagged because that can correctly close subsections and begin a new major section.

Does this prove WCAG conformance?

No. It checks selected source semantics and guidance related to headings. A complete accessibility evaluation requires rendered pages, keyboard and screen-reader testing, content judgment, and all applicable WCAG criteria.

How are role="heading" elements checked?

When enabled, the tool includes role="heading" elements and checks for a positive integer aria-level. Native H1-H6 markup is recommended when the code can be changed. Levels above 6 are shown for review because support can be inconsistent.

Can the checker detect CSS-hidden headings?

It detects hidden, aria-hidden="true", and inline display:none or visibility:hidden on a heading or ancestor. It cannot evaluate external stylesheets, class-based rules, responsive CSS, scripts, shadow DOM, or a live accessibility tree.

Why audit main content separately?

A full page can include recurring navigation, sidebar, and footer headings that are valid in their own landmarks but make an article outline harder to review. Main-content mode uses the first main element when available and clearly reports a body fallback otherwise.

Are IDs required on every heading?

No. Unique stable IDs are useful for table-of-contents links and deep links, but they are not required on every heading. Markdown IDs are not scored because each renderer may generate them differently.

Is pasted source uploaded?

The Pro workstation parses, scores, previews, and exports the source in the browser. The optional same-tab GEO handoff uses short-lived session storage and is offered only for source within 100,000 characters.