What are ARIA landmark regions?

Landmarks are the major sections of a page — main, navigation, banner, contentinfo, complementary, search, and form. Screen-reader users jump directly between them, so a complete and correct set of landmarks is one of the fastest ways to make a page navigable.

Why must there be exactly one main?

The main landmark identifies the page's primary content, and screen readers offer a shortcut to it. Having zero means there is no shortcut; having two or more makes the shortcut ambiguous. The checker flags both cases and also flags a main nested inside another landmark.

When do navigation landmarks need names?

A single nav needs no name. When a page has more than one nav — for example a primary menu and a footer menu — each needs an aria-label or aria-labelledby so a screen-reader user choosing from the landmark list can tell them apart.

What counts as orphaned content?

Headings, paragraphs, links, buttons, and form fields that are not inside any landmark are orphaned. Users who navigate purely by landmark can skip right past them, creating a navigation dead-end. The fix is to move that content into main or another region.

Is my HTML sent anywhere?

No. The page is parsed with the browser's DOMParser and every check runs locally, so your markup never leaves your device and the report appears instantly.

Landmark Region Completeness Checker

The Landmark Region Completeness Checker verifies that a page exposes the ARIA landmark regions screen-reader users rely on to navigate. Missing or misused landmarks create dead-ends: content that has no shortcut, ambiguous main regions, or duplicate menus a user cannot tell apart.

How it works

Map the landmarks. The HTML is parsed and every landmark is identified — main, nav, and aside always count; header and footer count only when they sit at the top level (a header inside an article is not a banner). Explicit role attributes are honoured.
Apply the rules. The checker confirms there is exactly one top-level main, a banner header, and a contentinfo footer; that any second-or-later nav has an accessible name; and that no headings, paragraphs, or controls sit outside every landmark.
Report. Each rule is marked as a pass, a suggestion (warn), or a problem (error) with a plain-language explanation of what to change.

Example

A page with <header>, <main>, a footer <nav>, and a <footer> passes the structural rules — but if both the header nav and the footer nav are unnamed, the checker flags that the two navigation landmarks cannot be told apart and recommends aria-label="Primary" and aria-label="Footer".

Tips and notes

Aim for one main, one banner, one contentinfo, and clearly named navs as the baseline on every template.
Wrap any floating widget or call-to-action in main or an appropriate region so landmark navigation does not skip it.
This is a structural check; pair it with the Screen Reader Announcement Simulator to confirm the regions are also announced sensibly.