Heading Structure Analyzer
Extract H1-H6 from HTML, view the heading outline as a tree, count per-level, and detect SEO issues: multiple H1s, missing H1, skipped levels, long headings, and empty headings. Export as markdown. 100% client-side.
About Heading Structure Analyzer
Extract H1-H6 from HTML, view the heading outline as a tree, count per-level, and detect SEO issues: multiple H1s, missing H1, skipped levels, long headings, and empty headings. Export as markdown. 100% client-side. Everything runs locally in your browser — your data never leaves your device.
How to use
- Enter your input in the tool above.
- Adjust any options to your preference.
- Use the Copy or Download buttons to save the result.
- Everything happens locally — your data never leaves your browser.
FAQ
Why does heading structure matter for SEO?
Search engines use headings to understand the topic and structure of a page. A clear H1 → H2 → H3 hierarchy helps crawlers and screen readers navigate. Common issues: multiple H1s (confusing), missing H1 (no clear topic), skipped levels (H2 → H4 breaks the outline), and headings over 60 characters (may be truncated).
How does the analyzer extract headings?
We use a regex to match <h1>…<h6> tags (case-insensitive, with attributes). The inner HTML is stripped of nested tags and decoded for entities, so the visible text is what we analyze.
What issues does it detect?
Five: (1) multiple H1 tags — best practice is one; (2) missing H1 — every page needs one; (3) skipped levels — e.g., H2 → H4 (don't skip for styling); (4) long headings over 60 chars; (5) empty headings with no text.
What extra features does this tool have compared to others?
(1) Heading tree visualization (H2 nests under H1). (2) Per-level count (H1-H6). (3) Word count per heading. (4) Five SEO issue detectors. (5) Markdown outline export. (6) Numbered outline export (1, 1.1, 1.2 form). (7) Copy outline to clipboard. (8) Long-heading (>60 chars) flagging. (9) History (localStorage, last 20). (10) Shareable URL — encode HTML in the fragment.
Can I fetch a URL to analyze?
Not directly — most websites block cross-origin fetches from the browser. Use your browser's View Source or DevTools, copy the HTML, and paste it here. This keeps the tool 100% client-side and offline-capable.
Is my data sent anywhere?
No. Heading extraction runs locally with regex. History is stored in localStorage on this device only.
Related tools
Affiliate Commission Calculator
Calculate affiliate commissions across four program types — flat percent, tiered percent (progressive brackets), recurring (monthly × N months), and hybrid (initial + recurring). Apply refund-rate and tax-withholding adjustments, compute effective commission rate, compare two program types side-by-side, and project break-even sales to hit a target income. History (localStorage) + shareable URL. 100% client-side.
Affiliate Link Cloaker & Redirect Generator
Cloak affiliate links into pretty URLs and generate redirect scripts (PHP, JavaScript, HTML meta refresh), plus .htaccess, nginx, and robots.txt rules. CSV import of slug/affiliate_url pairs, slug auto-generator from hostname, click-tracking parameter builder, URL-shortener compatibility check, history (localStorage), shareable URL. 100% client-side.
Anchor Text Distribution Analyzer
Analyze anchor text distribution from backlink data. Categorize anchors as exact/partial match, branded, generic, naked URL, or image. Compute distribution %, warn on over-optimization, and export. 100% client-side.