This audit checks that the width of the content on your page is equal to the width of the viewport. When content width is smaller or larger than viewport width, that's often a cue that the page is not optimized for mobile screens.
This audit is a roundabout way of determining if your page is optimized for mobile devices. If your site is not optimized and you want it to be, then see Responsive Web Design Basics to get started.
You can ignore this audit if:
- Your site does not need to be optimized for mobile screens.
- The content width of your page is intentionally smaller or larger than the viewport width.
The audit passes if
window.innerWidth === window.outerWidth.