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Heading Hierarchy & Document Outline Checker

Screen reader users rely on H1–H6 heading tags to navigate webpages efficiently. Use this tool to visualize your document outline, catch skipped heading levels, and fix logical structure issues.

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STRUCTURE & OUTLINE

Heading Hierarchy & Document Map

Screen readers construct an interactive outline using your H1–H6 tags. A logical outline lets users jump directly to sections without hearing the whole page.

Document Outline Tree4 headings
Valid Skipped Level
STRUCTURE ACCESSIBILITY GUIDE

Why Proper Heading Hierarchy Matters for Screen Reader Users

Screen readers like NVDA, JAWS, and Apple VoiceOver construct an interactive table of contents using HTML heading elements (<h1> through <h6>). A heading hierarchy checker helps web creators ensure that their pages provide a logical, predictable navigation outline for blind and low-vision visitors.

According to WebAIM screen reader surveys, over 70% of screen reader users skip through headings to locate relevant sections rather than reading entire pages sequentially. When developers skip heading levels—such as jumping directly from an <h1> main title to an <h4> subsection—assistive technologies report a broken outline, disorienting users.

How an Automated Heading Hierarchy Checker Works

Our heading hierarchy checker parses the HTML tree of a webpage, extracting all heading tags in sequential order. It flags structural violations such as multiple <h1> tags on a single page, empty heading elements used purely for visual spacing, and skipped heading levels (WCAG 2.2 Success Criterion 1.3.1 Info and Relationships).

Best Practices for Heading Structure

  • Single Main H1: Use exactly one <h1> per page representing the main topic or page title.
  • Sequential Nesting: Ensure H2 sections nest within H1, H3 subheadings nest within H2, and so on.
  • Style via CSS: Do not choose heading tags for text size; use CSS classes for typography and semantic tags for structure.

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