Heading Hierarchy Checker
Heading hierarchy (H1-H6) is one of the most frequent and fastest-to-fix accessibility non-conformities. It is also one of the least checked, because you need to read raw HTML. This tool does it in seconds.
Checks WCAG 2.4.6 compliance: unique H1, continuous levels, non-empty headings. Analysis runs entirely in your browser — no data is transmitted.
How to use this tool
- 1Enter the URL of the page to analyse
- 2Run the analysis
- 3Review the extracted heading structure
- 4Identify the hierarchy breaks flagged
Why it matters
Heading hierarchy is defined by WCAG 2.1 criterion 2.4.6 (Level AA) and RGAA criterion 9.1. An inconsistent structure (H3 after H1, missing H2) disorients screen reader users who navigate by heading to explore a page. It is also a structural quality signal for search engines. This criterion is frequently non-compliant because breaks are rarely visible without inspecting the HTML.
Frequently asked questions
Can a page have more than one H1?
No, according to WCAG and RGAA best practice: a page should have a single H1 describing its main content. In HTML5, multiple H1 elements are syntactically valid within separate sections, but accessibility guidelines and SEO best practice recommend a unique H1.
What is a heading level jump?
A level jump occurs when you go directly from H2 to H4 without an H3 in between. This breaks the logical hierarchy of the content and constitutes a WCAG 2.4.6 non-conformity.
Does heading hierarchy affect SEO?
Yes, indirectly. Google uses heading structure to understand how a page is organised. A missing H1 or inconsistent headings can affect how the page is indexed and how Google understands its main topic.