Missing H1
An H1 names what a page is about, for readers, screen readers and search engines alike. Why a page with none is harder to place, and how to fix it.
What it is
The <h1> is the top-level heading of a document: the one sentence that says what this page is. This check counts <h1> elements in the served HTML and fails when there are none.
It is a separate question from whether the page looks like it has a heading. A styled <div> at 48 pixels is a heading to a sighted reader and nothing at all to anything parsing the document.
Why it matters
A screen reader user navigating by heading gets no entry point into a page with no H1 — the outline they rely on to skim starts empty.
For a search engine it removes the clearest author-declared statement of the page's topic. The engine will infer one from the rest of the content, and inference is exactly the thing you do not want deciding what your page is about.
How to fix it
with a reference doc<h1>Main page heading</h1>Related checks
4This is one of the 75 checks the scanner runs. See what we check for the full list, every severity weight, and how the score is computed from them.