Spoke
Headings and document structure
Most people pick heading levels by how big they render. They're a document outline, and the difference shows up for exactly the readers you care about.
Heading semantics are an accessibility requirement with a published standard. That a single h1 is preferable is practitioner convention rather than an HTML rule.
Headings get treated as font sizes.
They're a document outline, and the difference shows up for exactly the readers you care about: people scanning, people using a screen reader, and anything parsing your page for structure.
Should a page have only one H1?
Yes, in practice. One h1 naming what the page is about, h2 for its main sections, h3 beneath those. HTML permits more and nothing breaks with two, but one top-level heading is what accessibility tooling expects, and it forces a useful discipline — if a page needs two h1s, it's usually two pages.
The stronger rule is don't skip levels. Jumping from h2 to h4 implies a layer of structure that doesn't exist, which confuses a screen reader and means nothing to a parser.
The outline test
Strip a well-structured page down to its headings and you should get a usable table of contents. Something a reader could scan to decide whether to read, and to find the bit they came for.
If the heading-only version reads as a list of disconnected phrases, the page doesn't have a structure. It has paragraphs with labels between them.
We generate the contents rail on every page from its h2 elements for exactly this reason. The rail is only useful because the headings are a real outline, and it would look visibly useless if they weren't. Cheap way to keep ourselves honest.
Levels are structure, not size
The most common defect: picking h3 because h2 renders too big.
Fix it in the stylesheet. A heading level says where a section sits in the document. Overload it with typography and your document structure ends up determined by your font scale — two things that should never have been connected.
Give them ids
Every heading should have a stable id. Costs nothing, and it makes each section individually addressable: a jump link, a shareable reference, a precise target for anything citing part of your page instead of all of it.
That last use is worth more than it used to be. When the thing being quoted is a passage rather than a page, having an addressable passage is a small structural advantage.
Where this meets AEO
The AEO section argues for question-shaped headings with answers underneath, and records Google's position that no particular style is required for its AI features.
Nothing on this page depends on that argument. Semantic heading structure is an accessibility requirement and a readability practice whether or not it affects retrieval — which makes it one of the few recommendations here that needs no ranking justification at all.
More in On-page & content
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Titles & descriptions
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Readability & formatting
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