H1 Checker — Heading Structure Analyzer
Paste a page's HTML to check its H1 and full H1-H6 hierarchy: missing or duplicate H1s, skipped levels, empty headings and outline problems. No signup.
- Free, no sign-up
- REST + MCP
- Updated
- Reviewed by Olgun Ozoktas
How to Use Heading Structure Analyzer
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Paste your HTML content
Copy the HTML source of any web page and paste it into the input area. You can paste a full page document or just a section containing headings. The analyzer works with any valid HTML. -
Review the heading tree
The analyzer extracts all H1 through H6 tags and displays them in an indented tree structure. Each heading shows its tag level, text content, and character count so you can quickly scan the hierarchy. -
Fix warnings and errors
Check the warnings panel for SEO issues like missing H1 tags, skipped heading levels, empty headings, and overly long heading text. Errors are high priority and warnings are recommendations for improvement. -
Use keyword highlighting
Enter a target keyword to see which headings contain it. This helps verify that your primary keyword appears in key headings like H1 and H2, which is an important on-page SEO signal.
Who Needs a Heading Analyzer?
SEO Professionals
Content Editors
Web Developers
Accessibility Auditors
Why Use Heading Structure Analyzer?
Heading tags (H1 through H6) are one of the most important on-page SEO elements. Search engines use them to understand the structure and hierarchy of your content, and screen readers rely on them for navigation. A well-structured heading hierarchy helps Google determine what your page is about and which sections are most important.
This analyzer parses your HTML and builds a visual tree of every heading on the page. It automatically detects common issues like multiple H1 tags, skipped heading levels (jumping from H2 to H4), empty headings, and overly long heading text. Each issue is flagged with a severity level so you can prioritize fixes.
The optional keyword highlighting feature shows which headings contain your target keyword, helping you verify that important SEO signals are in place. For a complete on-page audit, combine this tool with the Meta Tag Generator for title and description optimization, the SERP Preview to check how your page appears in search results, and the Keyword Density Checker for content-level keyword analysis.
How it compares
Heading analysis is typically bundled into paid SEO audit tools like Screaming Frog, Sitebulb, and Ahrefs Site Audit. These tools require monthly subscriptions and are designed for crawling entire websites, which is overkill when you need to quickly check a single page. Our analyzer is available, instant, and runs entirely in your browser with no data sent to any server.
Unlike browser extensions that only highlight headings on live pages, this tool works with any pasted HTML, including content from staging environments, local development servers, or CMS previews that are not publicly accessible. The warning system catches issues that simple heading extractors miss, like skipped levels and keyword presence.
Heading Structure Best Practices
- Every page should have exactly one H1 tag that describes the main topic. Multiple H1 tags dilute the primary heading signal and confuse search engines about the page's focus.
- Never skip heading levels. Go from H1 to H2 to H3 in order. Jumping from H1 to H3 creates gaps in the document outline that hurt both SEO and accessibility.
- Include your primary keyword naturally in the H1 and at least one H2. Search engines give extra weight to text inside heading tags when determining page relevance.
- Keep headings concise and descriptive. Aim for under 70 characters per heading. Long headings are harder to scan and may get truncated in some contexts.
- Use headings to create a logical outline of your content, not for visual styling. If you need larger or bolder text, use CSS classes instead of heading tags.