Why Does My WordPress Site Look Broken on Mobile?
Why This Happens
Theme developers test their own templates and default components thoroughly across screen sizes before release, but they have no way to anticipate every piece of custom content a site owner might add afterward. A wide table pasted into a post, an embedded video without a responsive wrapper, or a page-builder section using fixed pixel widths instead of relative units can all break the mobile experience even on an otherwise genuinely well-built responsive theme.
Common Culprits
- Wide tables or code blocks pasted directly into content without a scrollable wrapper, forcing the page to widen or causing horizontal scroll on mobile.
- Embedded videos or iframes without a responsive wrapper technique applied, which can display at a fixed size regardless of the actual screen width.
- Page builder sections using fixed pixel widths for columns or elements, rather than percentages or other relative units that adapt to the actual viewport.
- Large images without proper responsive image handling, forcing the layout wider than the screen rather than scaling down correctly.
- Custom CSS added over time that wasn't tested at every breakpoint, sometimes conflicting with the theme's own responsive rules in specific, narrow scenarios.
How to Diagnose and Fix It
- Use browser developer tools' device/responsive mode to identify exactly which element breaks and at what screen width.
- Wrap wide tables and embeds in a scrollable or responsive container rather than letting them force page width.
- Review any custom CSS or page-builder settings using fixed pixel widths, adjusting to relative units where appropriate.
- Test any new content added going forward across a few common screen widths before considering it finished.
Need mobile display issues found and fixed properly? See WordPress bug fix.