Read the H1–H6 Structure Without Fetching the Website

How to Use This Tool

Paste source HTML and expose its heading hierarchy locally. Extract an H1–H6 outline from pasted HTML locally for content review without crawling or sending the page to a server.

The failure HTML Heading Outline is designed to catch

Heading appearance in CSS does not determine semantic level; the actual h1 through h6 tags do. The boundary is the job stated in Read the H1–H6 Structure Without Fetching the Website; HTML Heading Outline is not intended to score or transform a different workflow.

The HTML Heading Outline input contract

The fields used for this specific operation are Input text, Unused option. Keep the source values beside the HTML Heading Outline result, because replacing the original would remove the evidence needed to reproduce or reverse the operation.

• For HTML Heading Outline, Input text starts at <h1>Guide</h1><h2>Setup</h2> in the worked case; replace that example with the matching source value.
• For HTML Heading Outline, Unused option starts at in the worked case; replace that example with the matching source value.

Worked result for HTML Heading Outline

The executable case called Default browser-only example expects out: H1: Guide H2: Setup. Verify that observation before entering real material, and then change one HTML Heading Outline field at a time so an unexpected direction or formatting change can be traced to a specific input.

Reading the HTML Heading Outline output

No. The transform runs in browser JavaScript and the page does not call a processing API. Network extensions or a compromised device remain outside this page's control. Apply that answer only when Input text, Unused option describe the same scope and format as the worked operation. If the source uses different units, quoting, nesting, timing or account rules, a plausible-looking HTML Heading Outline output is not sufficient validation.

Assumptions attached to HTML Heading Outline

• HTML Heading Outline assumes that the pasted input uses the syntax described by the selected standard or page guidance.
• HTML Heading Outline assumes that the operation is intentionally narrow and does not infer private downstream schema rules.

If one of these HTML Heading Outline assumptions is false, keep the result as a diagnostic rather than production or decision data, and choose an implementation that explicitly supports the missing rule.

Evidence maintained for HTML Heading Outline

The recorded reference is WHATWG HTML Living Standard. Reopen that source when the definition, format, fee or policy behind HTML Heading Outline changes; private configuration and downstream acceptance still have to be checked in the user's own system.

Where HTML Heading Outline runs

The named operation executes in browser JavaScript without an ecech calculation API. For HTML Heading Outline, local execution reduces transmission but does not control browser extensions, device security or the destination where the result is pasted, so sensitive inputs still require the user's normal handling rules.