Heading Tag Checker: See Your Page Outline

Headings are the table of contents of a page. Readers scan them to decide whether to stay, screen-reader users jump between them, and search engines and AI systems use them to work out which passage answers which question. When the outline is broken — no H1, five H1s, an H4 straight after the H1 — all three have a harder time.

This heading checker reads the page’s HTML and draws its H1–H6 outline as a tree. It flags a missing or duplicated H1, skipped levels, empty headings and headings that run too long, so you can repair the structure in minutes.

How to check your headings

1. Enter the page URL

   We fetch the server HTML and extract every heading from H1 to H6 in document order.

2. Read the tree

   Indentation shows nesting, so a heading that jumps two levels or sits under the wrong parent stands out.

3. Fix the flagged items

   Change the heading level in your editor or template, not just the font size, and check again.

What a healthy outline looks like

H1  Waterproof Hiking Boots for Women
  H2  How we tested
  H2  Best overall
    H3  Pros and cons
    H3  Who it fits
  H2  Best for wide feet
  H2  How to choose a waterproof boot
    H3  Membrane vs treated leather
    H3  Sizing and break-in
  H2  Frequently asked questions

One H1 states the topic. H2s split it into the main sections, and H3s sit only inside an H2. Going down, levels move one step at a time; going back up, you can jump any number of levels when a new section starts. That is the pattern the W3C headings tutorial recommends for accessibility.

Common heading problems and how to fix them

• No H1. Often the page title is styled text or an image. Make the main title a real <h1>.
• Several H1s. Many themes wrap the logo or site name in an H1 on every page. Google has said multiple H1s aren’t a problem for Search, but one clear H1 is better for accessibility and leaves no doubt about the topic.
• Skipped levels, such as an H2 followed by an H4. Usually a heading was picked for its size. Fix the level and change the look in CSS.
• Empty headings left by page builders or icon-only headings. Screen readers announce them as blank headings.
• Overlong headings, where a whole paragraph was marked as a heading. Keep headings to a short line.
• Headings used for layout: “Follow us”, “Newsletter” or a footer full of H4s. Use a paragraph or a div with a class instead.

<!-- Wrong: level chosen for size -->
<h4 class="big">Our services</h4>

<!-- Right: level chosen for structure, size set in CSS -->
<h2 class="section-title">Our services</h2>

Headings, SEO and AI answers

Headings aren’t a magic ranking lever, but they shape how a page is understood. A heading tells search engines what the passage beneath it covers, and Google can rank individual passages for specific queries. AI answer engines work in a similar way: a heading phrased as a question, followed by a direct answer, is an easy passage to extract and cite. That answer-ready structure is one of the signals in the AI SEO checker.

The old idea that every <section> can restart at H1 came from the HTML5 “outline algorithm”, which browsers never implemented and which was removed from the HTML standard in 2022. Use explicit levels; MDN’s heading reference covers the details.

Your H1 should match the promise of the title tag without copying it word for word, and your H2s should cover the subtopics searchers expect. Review the rest of the page with the on-page SEO checker.

Tips for a clear heading structure

• Draft the H2s first when you plan a page; if they read like a sensible table of contents, the structure is right.
• Phrase some H2s the way people ask questions, and answer each one in the first sentence below it.
• Remove heading tags from sidebars, footers and widgets so the outline reflects only the main content.
• Make each heading specific — “Pricing for teams” says more than “Details”.
• Check templates, not just pages: one wrong heading level in a theme repeats on every page.

Limits to keep in mind

The checker reads headings from the server HTML, so headings inserted by JavaScript after the page loads won’t appear, and it can’t tell whether a heading is hidden with CSS. It judges structure, not whether the wording is helpful. To compare your outline with a page that outranks you, use the SEO comparison tool; for accessibility beyond headings, run Lighthouse in Chrome DevTools.

Last updated Oct 30, 2026 by the Yes SEO team.