This translation has not been editorially reviewed yet. The German version is authoritative. Deutsche Fassung →
Don't lock zoom: user-scalable=no excludes people
Anyone who can only enlarge text via browser zoom has no fallback if zoom is locked. What's evaluated is the content of the viewport meta tag: user-scalable=no locks it, and a maximum scale under 2 prevents the 200 percent WCAG 1.4.4 requires.
- The lock is usually set to prevent accidental zooming during use — well-intentioned, but its effect is exclusion. Current browsers partly ignore the setting; older and embedded views still honour it.
- The finding lands in the Accessibility audit area under 1.4.4, even though the cause sits in the viewport meta tag — the effect decides the categorisation, not the location in the source code.
- A MISSING viewport meta tag is explicitly not a zoom finding here. There's a separate rule for that in the SEO audit area; two findings for the same cause would be a double count at the expense of the audited website.
FAQ
Which values count as a zoom lock?
user-scalable with the value no, 0, or false — and a maximum scale under 2, because that makes the required 200 percent zoom unreachable.
Isn't the lock ineffective anyway?
Only partly. Several current browsers ignore it; others and embedded web views still honour it. Relying on it being ignored means leaving accessibility up to the visitor's browser.