How this tool works
Parses the HTML as an inert browser document, collects heading elements in source order, and flags skipped numeric levels.
How to use it
- Paste the relevant HTML source.
- Review heading text, sequence, and flagged level jumps.
- Compare the outline with the page’s actual sections and reader flow.
Limits to keep in mind
It analyzes only the snippet you paste. It cannot evaluate visual styling, the full rendered DOM, or whether headings accurately summarize the content.
Frequently asked questions
Does every page need exactly one H1 to rank?
This checker reports structure; it does not claim a ranking rule based on a specific H1 count.
Does it inspect my live page?
No. Paste the source you want reviewed.
Is skipping a heading level a problem?
It is not a ranking penalty, but it can make the outline harder to follow for readers and assistive technology. Use levels to show real hierarchy, not for font size.
Can a page have more than one H1?
HTML allows it and search engines handle it, but one clear H1 describing the page keeps the outline simple and easier to maintain.
What the heading outline reveals
Headings are the titles and subtitles inside a page, written in HTML as h1 to h6. Together they form an outline, like the table of contents of a document. Readers skim headings to decide whether a page has what they need, and screen reader users often move through a page by jumping from heading to heading.
The Heading Structure Checker reads the HTML you paste, finds every heading element in the order it appears in the source, and shows them as an outline with their levels. It flags places where the numeric level jumps, for example from an h2 straight to an h4. This gives you a quick view of how the page is organized, without having to read through the markup. The tool works as a local check on the text you provide. It does not open your live page.
Review hierarchy and meaning
A clean outline has one main heading that names the page, major sections as h2, and sub-points inside those sections as h3, and so on. Levels should show real structure, not size or style. If you want text to look bigger, use CSS, not a heading tag, and if a heading is just a decorative line, it may not need to be a heading at all.
Read the outline as if it were the only thing you could see. Does it describe the topic clearly, in a logical order, with each section name telling you what is inside? Headings like "More" or "Info" are vague, while "How to submit a sitemap" is useful. Search engines use headings as one of several clues about page structure, but the main benefit is for people, who find the page easier to scan.
About the single H1 question
Many guides say a page must have exactly one h1. In practice, HTML allows more than one, and Google has said it can handle pages that use several. Still, one clear h1 that matches the main topic of the page is a simple and reliable habit. It keeps the outline easy to understand for readers, assistive technology and the people who maintain the site.
Use the checker to see how many h1 elements the pasted markup contains. If the count is zero, consider whether the page has a clear title heading. If it is more than one, check whether the extra ones are real section titles that should be h2, or part of a logo, a banner or a widget. Templates often add headings in menus, sidebars and footers that you may not intend.
Skipped levels
A skipped level happens when a heading jumps down by more than one step, such as an h2 followed by an h4. It is not a ranking penalty and does not break a page. It does, however, suggest that the structure may be confusing, and it can make navigation harder for people who rely on headings to understand how content is nested.
Often the fix is simple. Change the h4 to an h3 if it belongs directly under the h2, or add the missing h3 section if one is genuinely absent. Do not add empty headings just to remove the warning. Going back up is fine. A page can move from an h4 to a new h2 when a new major section begins. The flag marks places worth checking, not definite errors.
What the checker cannot assess
The tool looks at the pasted snippet only. It does not know about visual styling, whether a heading is hidden, whether a heading is added later by JavaScript, or whether the heading text accurately describes the content below it. Those need human review.
If your page builds headings with scripts, paste the rendered HTML from your browser's developer tools, not the original page source, so the tool can see the final result. Also keep in mind that a page builder or theme may add headings you did not write. A passing result means the numeric levels follow in sequence, not that the page is well written or well organized. Use it as a prompt for editing, not as a verdict.
Use findings in an editing workflow
A good routine is to run the checker on a page before publishing, or when you update an old article. Look at the outline, fix level jumps, tighten vague headings, and check that the main keyword or topic appears naturally in the h1 and the key section headings without repetition.
For longer articles, the outline also shows balance. If one section has twenty sub-headings while others have none, the page may need reorganizing. If you are rewriting content, compare the outline before and after to make sure you kept all the important sections. Share the outline with writers and editors, because it is a quick way to agree on structure before polishing sentences.
Accessibility and quality benefits
Well-structured headings help users of screen readers, who can list headings and move directly to the part they want. They also help people who use browser reading modes, translation tools and keyboard navigation. Good structure is part of basic accessibility under the Web Content Accessibility Guidelines.
The checker is not an accessibility audit, but it covers one important piece. Combine it with other checks, such as image alt text, link text and form labels, which you can review with other tools on this site. A page that is easy to scan, easy to navigate and clearly organized serves every reader better, and that kind of quality tends to support your search performance over time.
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