Paste HTML or load a URL to visualize its heading hierarchy and catch skipped levels, missing or duplicate H1s, and other structural issues.
Loading a URL requires the target site to allow cross-origin requests (CORS). Many sites block this by default — if fetching fails, copy the page's HTML source and use "Paste HTML" instead.
Paste HTML or load a URL, then click Analyze to see the heading outline here.
Part of One File Tools. Parsing happens entirely in your browser.