Header tags SEO: how to structure H1 to H6 for readers, Google and AI answers

Header tags, properly called heading tags, are the <h1> to <h6> elements that title a page and its sections. For header tags SEO the honest summary is short: Google uses headings to understand what each part of a page is about, it does not care whether they are in perfect order, and no heading level carries a published ranking weight. What headings do decide is whether people can skim the page, whether screen reader users can find their way around it, and where a page splits into passages that an AI answer can lift.

This guide covers what each level is for, the hierarchy rules from the HTML standard and the W3C, what Google and Microsoft say about headings, when a heading should be a question, and real outlines from four well-known sites. To see any page’s outline the same way, paste it into the free heading checker.

WebAIM’s survey had 1,539 valid responses from screen reader users; WebAIM notes the sample was not controlled^[10]. The level rule is from the HTML standard’s section on headings and outlines^[6].

What header tags are, level by level

MDN’s definition: “The <h1> to <h6> HTML elements represent six levels of section headings. <h1> is the highest section level and <h6> is the lowest.”^[7] The HTML standard defines a page’s outline as “all headings in a document, in tree order”, and says it should be used for things like generating tables of contents^[6]. In other words, your headings are the page’s table of contents, whether you show one or not.

The H1 has its own guide: what an H1 tag is, and how many to use. The H1 is often confused with the title tag, which is covered in title tags. One naming note: in HTML, <header> is a different element, a container for introductory content such as a logo and menu. When SEO people say “header tags”, they mean headings.

<h1>Running shoes for beginners</h1>          <!-- the page's subject, once -->
  <h2>How do I choose my first pair?</h2>      <!-- a section -->
    <h3>Cushioning</h3>                         <!-- a part of that section -->
    <h3>Heel-to-toe drop</h3>
      <h4>What drop suits heel strikers?</h4>   <!-- a detail inside a part -->
  <h2>Our picks</h2>                           <!-- back up to a new section: fine -->
    <h3>Best overall</h3>
  <h2>When should I replace running shoes?</h2>

What Google says about headings

Google’s statements are consistent, and more modest than most SEO advice.

• Headings help Google understand content. John Mueller, in a hangout reported by Search Engine Journal in January 2020: “We do use headings when it comes to search. But we use them to better understand the content on the pages.” And: “it’s not so much that suddenly your page ranks higher because you have those keywords there.” He also called headings “a bit overrated”^[2].
• Order doesn’t matter to Google. The SEO Starter Guide, under things not to focus on: “Having your headings in semantic order is fantastic for screen readers, but from Google Search perspective, it doesn’t matter if you’re using them out of order.” And: “There’s also no magical, ideal amount of headings a given page should have.”^[1]
• Headings help readers, so use them. The same guide asks you to “break up long content into paragraphs and sections, and provide headings to help users navigate your pages”^[1].
• Headings feed the title link. Google lists heading elements among the sources for the clickable headline of a search result, and when a page has several equally prominent headings it “may use the first heading as the text for the title link”^[3].

Heading hierarchy: the rules that matter

Three sources agree on the rule, and the HTML standard has recently made it strict.

The W3C’s accessibility tutorial: “Nest headings by their rank (or level).” Headings of equal or higher rank start a new section; lower rank starts a subsection. “Skipping heading ranks can be confusing and should be avoided where possible: Make sure that a <h2> is not followed directly by an <h4>, for example. It is ok to skip ranks when closing subsections”^[8].

The HTML standard: “Each heading following another heading lead in the outline must have a heading level that is less than, equal to, or 1 greater than lead’s heading level.” It also says that if a document has headings, at least one should be level 1^[6]. So an H2 followed by an H4 is not only unhelpful, it is non-conforming HTML.

MDN: “Do not use heading elements to resize text. Instead, use the CSS font-size property.” and “Do not skip heading levels”. It explains why: screen reader users “quickly jump from heading to heading”, and a missing level leaves them “wondering where the missing heading is”^[7].

/* Want a smaller heading? Change the size, not the level. */
h2.compact { font-size: 1.125rem; }

/* Not: <h4> used because it looks smaller.
   Yes: <h2 class="compact"> where a section starts. */

Two cases that look like mistakes and aren’t

Going back up. An H4 followed by an H2 just closes the subsection and starts a new section^[8].

Fixed page areas. The W3C tutorial makes an exception for sidebars and similar regions: their heading ranks “should not change depending on the ranks in the content area”, because consistency across pages is more important^[8]. It also shows both common layouts as acceptable: the H1 first with navigation headings one level below, or navigation first with the content heading as the H1.

Why it matters: accessibility

In WebAIM’s survey of screen reader users, 71.6% said that to find information on a long page, their first move is to navigate through the headings, against 13.6% who use the find feature and 6.4% who read the page through. 88.8% found heading levels very or somewhat useful^[10]. WCAG 2.2 Success Criterion 2.4.6 (Level AA) asks that “headings and labels describe topic or purpose”; it doesn’t require headings, but it requires the ones you have to be descriptive^[9]. A heading list that reads “Overview, Learn more, Learn more” fails that test.

Headings and AI answers

Here the two biggest search companies say slightly different things, and both are worth hearing.

Microsoft, writing for Bing in October 2025: “Headings are HTML tags (<h2>, <h3>) that mark where one idea ends and another begins. For AI, they act like chapter titles that define clear content slices.” Its example replaces a vague “Learn More” heading with “What Makes This Dishwasher Quieter Than Most Models?”. It adds that “Direct questions with clear answers mirror the way people search” and that assistants “can often lift these pairs word for word”, while saying there is “no secret sauce that guarantees selection in AI answers”^[5].

Google, in its guide to its AI features, lists “headings that provide a clear structure to navigate content” as part of organising content for readers, and then, under things you can ignore: “There’s no requirement to break your content into tiny pieces for AI to better understand it. Google systems are able to understand the nuance of multiple topics on a page and show the relevant piece to users.”^[4]

Read together: write headings that tell a reader exactly what each section holds, and don’t chop a page into fragments for machines. A descriptive heading over a section that answers it is good for both. A page cut into thirty two-sentence sections to “feed” AI is not something either company asks for.

When a heading should be a question

The GEO Audit, the 31-check page audit behind our free checkers, has three heading checks, and one of them is about questions. As coded:

• Exactly one H1 passes when the page has one <h1>, not zero and not two.
• Clear heading hierarchy passes when the page has at least two <h2> headings, so the content is split into sections at all.
• Question-shaped headings looks at every H2, H3 and H4. A heading counts as a question if it contains a question mark or starts with how, what, why, when, which, who, is, are, can, does, do or should. The check passes when at least one heading is a question, and reports the share, such as “3 of 12 headings are questions”.

The bar is deliberately low: one question heading passes. The reason for the check is the Microsoft point above. People ask assistants questions, so a section headed with the question it answers, with the answer in its first sentence, is a passage that matches a prompt. That is reasoning, not a published ranking rule; no AI company documents that it rewards question headings.

Here is the same page outline before and after, scored with the audit’s own question rule. Before: 0 of 5 headings are questions, an H2 jumps to H4, and two headings say “Learn more”. After: 3 of 6 are questions, no level is skipped, and every heading names its section.

<h1>Acme Payroll</h1>
  <h2>Overview</h2>
      <h4>Features</h4>
      <h4>Pricing</h4>
  <h2>Learn more</h2>
  <h2>Learn more</h2>

<h1>Payroll software for small UK businesses</h1>
  <h2>What does Acme Payroll do?</h2>
    <h3>Pay runs and payslips</h3>
    <h3>HMRC filing</h3>
  <h2>How much does it cost?</h2>
  <h2>Does it work with Xero?</h2>
  <h2>Customer stories</h2>

Note what stayed a label: “Pay runs and payslips” and “Customer stories” read better as labels than as forced questions. Turn a heading into a question when the section answers one people actually ask; the People Also Ask guide shows how to find them. And answer it at once: a question heading followed by three paragraphs of preamble is worse than a label. The readability checker tests whether an opening sentence works as a quotable answer.

Real outlines from four sites

We ran four public pages through the code behind the heading checker on 11 October 2026. It reads the HTML the server sends, without running JavaScript, as most AI crawlers do. None of these is a model to copy or avoid wholesale; each shows one point.

The WordPress case touches a common worry. Google’s spam policies list “Text that’s only accessible to screen readers and is intended to improve the experience for those using screen readers” among things that don’t violate them. What they rule out is text hidden “solely to manipulate search engines”, such as white text on white or text positioned off-screen^[11]. A keyword-stuffed H1 hidden from view is the second kind.

Common heading problems and fixes

Checking headings across a site

The checker reads one page. CoreCited’s Site Audit runs the three heading checks above on every page it crawls, with each failing page listed, so a template problem shows up as one pattern instead of a hundred surprises. The free account audits 10 pages; every limit is on the pricing page.

Questions people ask

Sources