Heading Analyzer

How to use it

1. Paste a page source or a Markdown document into the input box. If the text contains h1 to h6 tags it is read as HTML; otherwise lines starting with one to six # signs are read as Markdown headings.
2. The heading tree lists every heading in document order, indented by level, so the outline reads at a glance.
3. The issues list flags structural problems: no h1, more than one h1, a level jump such as h2 followed by h4, an empty heading, or a heading longer than 60 characters.
4. The counts row shows how many headings sit at each level, and the copy button puts the tree, counts and issues into a plain-text report.
5. Everything runs in your browser. Nothing is uploaded, and no request leaves the page.

Common use cases

• Auditing a page before publishing - check that the outline matches the content and that exactly one h1 carries the page topic.
• Reviewing imported Markdown - pasted documents often carry deep jumps or leftover empty headings from old exports.
• Teaching document structure - show how a logical outline maps onto heading levels in a class or workshop.
• Cleaning up templates - spot duplicated h1 tags across a set of generated pages.

Why it stays private

The analyzer parses the pasted text with the browser's own HTML parser plus a few regular expressions. No network request is made, no content is stored, and clearing the box removes every trace from the page.

FAQ

Q: Which heading syntaxes are supported? A: Markdown ATX headings, one to six # signs followed by a space, and HTML h1 to h6 tags. Headings inside fenced code blocks are ignored so that documentation samples do not pollute the outline. Setext headings, the underline style, are not parsed.

Q: Does a missing h1 hurt rankings? A: Search engines can usually work out the page topic without an h1, and this tool makes no promise about rankings. A single clear h1 is a widely used convention that helps readers and assistive technology, which is why it is reported.

Q: What does a skipped level mean? A: Going from h2 straight to h4 skips h3. It is not a formal error in the HTML specification, but it often signals a broken outline or a copy-paste accident, so it is listed as an issue.

Q: Why is a long heading only a warning? A: Titles longer than about 60 characters are frequently truncated in search result listings, so the tool notes the length. Whether to shorten it is an editorial decision, not a rule this tool enforces.