Multi-device responsive layout tester in your browser. Inspect mobile, tablet, and desktop viewports, switch orientations, zoom frames, and test live layouts in side-by-side split screens.
Runs entirely in your browser
Checking a site at several screen sizes usually means resizing your browser over and over. This viewer shows a live URL in multiple simulated viewports at once — phone, tablet and desktop — side by side, with orientation switching and zoom, so you can see how a layout responds across devices in a single glance.
Viewing breakpoints simultaneously makes responsive problems obvious: a heading that wraps badly on mobile, a grid that breaks on tablet, spacing that only works on desktop. It is far quicker than toggling one size at a time and easy to miss issues that way.
It runs in your browser. Use it while building or reviewing responsive layouts to catch breakpoint issues early, or to demonstrate how a page looks across devices. Note that some sites restrict being embedded in a frame, which can limit previewing those specific pages.
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