24 Viewports.
One Click.
Responsive Design Tester
One click opens a responsive testing panel. Pick a device. See the exact viewport. Test instantly—and find elements breaking your layout.
24 viewports. Overflow detection built in.
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Detects Overflow Elements
World First Browser OS
Launch from Quick Launch
150+ Tools
Test Viewports.
Find Breakage.
The only responsive tester that shows you what’s breaking.
Client says “it looks broken on my phone.” You open Chrome DevTools, resize the viewport, and squint at the screen trying to spot the problem. It takes forever.
This tool shows you 24+ device presets—iPhone, iPad, Galaxy, Desktop—in a sleek testing panel. But that’s not the killer feature.
Debug mode finds overflow elements automatically.
Press D to activate. The tool scans every element in the viewport and highlights anything causing horizontal scroll:
- Elements wider than the viewport
- Fixed-position elements extending past edges
- Absolutely positioned content breaking boundaries
Red borders show exactly which elements are the root cause. A side panel lists them all. Click to jump directly to the problem.
Stop guessing. See what’s broken. Fix it.
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