Heading Hierarchy checker
Analyze whether headings form a clear, logically ordered document outline.
How to use the Heading Hierarchy checker
What does the Heading Hierarchy checker do?
Analyze whether headings form a clear, logically ordered document outline; It applies this page-specific rule: analyze whether headings form a clear, logically ordered document outline.
Which inputs does this tool use?
To analyze whether headings form a clear, logically ordered document outline, enter Input, Result; keep every value in the same example; select Check input when the values are ready; Start with a familiar case covered by this rule - Enter the value or list you want to check in the labeled controls - so the expected result can confirm the settings.
How should the tool result be read?
For a result intended to analyze whether headings form a clear, logically ordered document outline, enter the value or list you want to check in the labeled controls; read result together with the original input rather than as an isolated answer, and confirm that its units or structure match the intended use.
Is more than one h1 always an error?
When the goal is to analyze whether headings form a clear, logically ordered document outline, this implementation extract h1 through h6 elements or a pasted heading list, build an outline, and flag skipped levels, empty headings, multiple top headings, and abrupt hierarchy changes.
Why are skipped heading levels a problem?
When using the page to analyze whether headings form a clear, logically ordered document outline, the tool handles only the format and rules described on this page.
Limits and accuracy
When using this tool to analyze whether headings form a clear, logically ordered document outline, your work is processed in this browser tab; a passing result confirms the rules tested on this page, but it does not prove that an address, identifier, account, or remote resource exists; keep input until the output has been checked in its intended destination.
What Heading Hierarchy checker does
Analyze whether headings form a clear, logically ordered document outline.
Enter the value or list you want to check in the labeled controls. The Heading Hierarchy checker result stays separate so you can review it before copying, downloading, or using it elsewhere.
Your work is processed in this browser tab. Keep the original whenever a conversion changes formatting, dimensions, or precision.
Frequently asked questions
Is more than one h1 always an error?
This implementation extract h1 through h6 elements or a pasted heading list, build an outline, and flag skipped levels, empty headings, multiple top headings, and abrupt hierarchy changes. The output is visual outline, heading counts, source references, and hierarchy warnings.
Why are skipped heading levels a problem?
The tool handles only the format and rules described on this page. It focuses narrowly on document heading order and structure rather than all ARIA or HTML rules. It does not contact a remote validation or lookup service.
Can I analyze a plain list without HTML?
Input is processed by JavaScript in the current browser tab. Nothing entered in the tool is sent to Plain Tools; keep the original when the transformation is lossy.