Header tags
The H1 to H6 HTML elements that define a page's heading hierarchy for readers, screen readers and retrieval systems.
In depth
What it really means
Header tags mark structure, not styling. H1 is the page’s subject, H2s are its main sections, H3s are subsections. Screen readers use them to let users jump between sections, which is why skipping levels breaks accessibility.
Their weight has grown with AI search. Retrieval systems split pages on heading boundaries, so your H2s effectively define the chunks that compete for citation. A heading phrased as the question it answers is worth more than one phrased as a label.
How it works
- Headings define the document outline in HTML.
- Screen readers expose that outline for navigation.
- Retrieval systems commonly split content at heading boundaries.
- Each resulting section is indexed and scored independently.
Pros & cons
Pros
- Directly shapes how your page is chunked for retrieval.
- Required for accessible navigation.
- Improves human skim-reading, which is how most people read.
Cons
- Weak direct ranking effect on its own.
- Often controlled by the CMS template rather than the writer.
- Easy to break by styling with headings instead of CSS.
Common mistakes
- Using heading tags for visual size rather than structure.
- Skipping levels, such as H2 straight to H4, which breaks the outline.
- Headings that label the page rather than name the reader’s question, like ‘Overview’ or ‘Key considerations’.
- Multiple H1s where the CMS adds one and the writer adds another.
Best practices
- One H1 per page, stating the subject.
- Phrase H2s as the question the section answers.
- Never skip levels.
- Use CSS for size, headings for structure.
- Read your headings alone as a list. They should form a usable outline of the page.
FAQs
What are header tags?
The H1 to H6 HTML elements defining a page’s heading hierarchy for readers, screen readers and retrieval systems.
How many H1 tags should a page have?
One. HTML5 technically permits more, but a single H1 keeps the outline unambiguous for screen readers and retrieval systems.
Do header tags affect rankings?
Weakly on their own. Their real value now is that retrieval systems split pages at heading boundaries, so your headings determine which chunks compete for AI citations.
Keep reading
Related on LymLyt
Beyond LymLyt
Further reading
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