meta-viewport-large
Viewport meta tag should allow zooming up to 500%
Checks that <meta name="viewport"> does not set user-scalable=no or maximum-scale below 5 (500%).
Applies to. Applies to <meta name="viewport"> elements that carry a non-empty content attribute, in a page of its own: browsers ignore one in a document shown in a frame.
Expectation. The content attribute does not block zoom with user-scalable, and does not set maximum-scale below 5 (500%), read as browsers read it, the same way meta-viewport-zoom-enabled reads it. This is the AAA-level, stricter counterpart of meta-viewport-zoom-enabled (which enforces the AA 200% minimum as a hard, WCAG-normative fail); this rule is advisory best-practice guidance toward the higher AAA bar.
What a finding reports.
reasons: each setting in the content attribute that limits zoom, as written there in lowercase, such asuser-scalable=noormaximum-scale=2(below 5).
These data.details fields help to read and reproduce a finding. Apart from reasonCode and the few fields Output schema names as stable, they are not a stable contract: a field may be renamed or dropped in a minor release, so don’t build on them.
Examples
<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=5">
maximum-scale=5 (500%) already meets the best-practice ceiling this rule checks toward.
<meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no">
user-scalable=no blocks zooming past whatever scale the page loads at, short of the AAA 500% best-practice target.
How to check
When this rule can’t decide, it reports cantTell and leaves the question to a person. Each question it can ask is listed here under its reason code, with the steps to answer it. A finding carries the same steps as howToCheck, in the scan’s language. See Output schema.
VIEWPORT_ZOOM_BELOW_500
- Read the viewport meta tag's content in the page source; the report lists the settings that limit zoom, such as user-scalable=no or maximum-scale=2.
- Open the page on a phone or in the browser's device emulation and pinch-zoom (or use the zoom gesture) as far as it will go.
- Note whether it reaches 500% and whether text is still readable.
Pass. The page can be zoomed to 500% with no user-scalable=no and no maximum-scale below 5.
Fail. Zoom is blocked or stops below 500%, which misses the best-practice target beyond WCAG 1.4.4.