📋 Paste HTML

Paste any HTML (full page source or a snippet).

Tip: Page source can be opened with Ctrl+U in most browsers. The tool extracts only the heading elements from whatever is pasted.

🌳 Outline

Issues are flagged inline. The outline can be copied as Markdown or plain text.

Paste HTML on the left to see the outline.

FAQ

What this tool does

What is a heading outline and why does it matter?

The H1–H6 headings on a page form a hierarchical outline of its content. Screen readers, search engines, and AI crawlers use this structure to understand the page. A clean outline (one H1, logical H2s, optional H3s nested under them) helps both accessibility and SEO. A messy one (multiple H1s, jumping from H2 straight to H5) makes the page harder to parse.

What issues does this tool flag?

General questions

How does the parser work?

The browser's built-in DOMParser reads the HTML you paste, then the tool walks the document in document order, picking up every h1h6 element. Hidden headings are detected by checking inline style attributes and certain aria-hidden flags. The parse is forgiving; partial HTML works fine without a full document.

What does "Copy as Markdown" produce?

A clean Markdown outline using # for H1, ## for H2, and so on. The same convention Markdown uses for headings.

Does this work for HTML fragments?

Yes. You can paste just a section of HTML. The parser doesn't require a full document, <html>, <head>, or <body> tags.

Does this tool send my data anywhere?

No. Everything runs in your browser. The HTML you paste never leaves your device.

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