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browserutils

Heading Hierarchy Checker

Check HTML heading structure for proper nesting

Heading Hierarchy Checker is a free online tool from BrowserUtils that check html heading structure for proper nesting. It runs entirely in your browser — your data never leaves your device. No account required.

How to use Heading Hierarchy Checker

  1. 1 Paste or type your input into the editor above.
  2. 2 The tool processes your data instantly — right in your browser, with nothing sent to a server.
  3. 3 Copy the result with one click or continue editing your input.

About Heading Hierarchy Checker

Free online heading hierarchy checker. Paste HTML and validate that h1-h6 headings follow proper nesting order for accessibility and SEO best practices. This tool runs entirely in your browser — your data is never sent to a server. Just paste your input, get instant results, and copy with one click. No sign-up or installation required.

Heading Hierarchy Checker specs

Runtime
100% client-side (browser)
Built on
WCAG 2.2 contrast formulas (relative luminance per W3C spec) and ARIA 1.2 role mappings
Cost
Free — no account, no rate limits, no usage caps
Browser support
Chrome 90+, Firefox 88+, Safari 14+, Edge 90+
Part of
299 developer tools on BrowserUtils (100% client-side)

Questions

Why does heading hierarchy matter for accessibility?
Screen reader users often navigate pages by headings. A logical heading hierarchy (h1 followed by h2, then h3, etc.) creates a clear document outline that allows users to understand page structure and jump to relevant sections efficiently.
Can I have multiple h1 elements on a page?
While HTML5 technically allows multiple h1 elements in sectioning content, it is best practice to use a single h1 per page for clarity. Multiple h1 elements can confuse screen readers and dilute SEO focus.
How do I use the heading hierarchy checker?
Paste your HTML into the input area and the tool will extract all h1-h6 elements, display their nesting structure, and flag any skipped levels (e.g., jumping from h2 to h4) that violate best practices.
Is it okay to skip heading levels like going from h2 to h4?
No. Skipping heading levels breaks the document outline and confuses assistive technology users. Always step down one level at a time (h2 to h3, not h2 to h4). You can step back up to any higher level when starting a new section.
Does this heading hierarchy checker store my HTML?
No. The HTML you paste is analyzed entirely in your browser. Nothing is sent to a server or saved beyond your current session.
Embed this tool

Copy this code to embed the tool on your website. Adjust the height to fit your layout.

<iframe src="https://www.browserutils.dev/embed/heading-hierarchy-checker" width="100%" height="500" frameborder="0" title="Heading Hierarchy Checker"></iframe>

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