On-Page SEO Foundations

Single H1 heading

Also known as H1 · main heading · primary heading

The <h1> is the top-level heading that names the page's main topic; using exactly one gives the document a clear, unambiguous title for users, crawlers, and assistive technology.

What it is

Headings <h1> through <h6> define the outline of a page. The <h1> sits at the top of that hierarchy and should state what the whole page is about, with subsequent sections nested under <h2> and <h3>.

Why it matters

A clear single H1 reinforces the page's topic and helps crawlers and AI engines parse the document outline to extract the right answer. A logical heading structure also makes content easier to chunk and quote, which improves how passages are pulled into AI-generated answers.

How to verify

Use browser DevTools or run document.querySelectorAll('h1') in the console to count H1 elements, expecting exactly one. Accessibility tools like the WAVE or Lighthouse heading-order checks also flag missing, empty, or duplicate H1s.

How to fix

Keep one descriptive <h1> per page that mirrors the page topic and is close to the title tag, then demote any extra H1s to <h2> or <h3>. Maintain a logical, non-skipping heading order and avoid using headings purely for visual sizing.

In the checklist

This concept maps to a check in the GEO Score checklist.

Use the checklist

Related terms

Official references

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Put this into practice.

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