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📋 Responsive Breakpoints Reference
| Breakpoint | Min Width | Target Device |
|---|---|---|
| xs | 0px | Small phones |
| sm | 576px | Large phones/Tablets |
| md | 768px | Tablets |
| lg | 992px | Small desktop/Laptop |
| xl | 1200px | Desktop monitor |
| xxl | 1400px | Large desktop |
Free online responsive design tester. Enter a URL to preview how it looks on mobile, tablet, laptop, and desktop screens. 100% client-side, nothing uploaded to any server.
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| Breakpoint | Min Width | Target Device |
|---|---|---|
| xs | 0px | Small phones |
| sm | 576px | Large phones/Tablets |
| md | 768px | Tablets |
| lg | 992px | Small desktop/Laptop |
| xl | 1200px | Desktop monitor |
| xxl | 1400px | Large desktop |
Free online responsive design tester to help front-end developers and designers quickly check how websites render on different screen sizes. Supports multiple presets including phone, tablet, laptop, and desktop, as well as custom dimensions.
Enter the URL you want to test in the input field (pre-filled with the Free ToolBase homepage), then click a device preset or adjust the width/height manually. The preview area resizes automatically. Click "Load" to refresh the preview. Some websites may not load due to X-Frame-Options restrictions — this is normal behavior.
Yes. Besides the presets for mobile/tablet/desktop, you can manually enter any width and height for custom testing.
Some websites set X-Frame-Options: SAMEORIGIN or Content-Security-Policy headers that prevent loading in an iframe. This is the website's own security policy, not a problem with this tool.
Everything runs locally in your browser. The URL you enter is only used to load the preview and is not uploaded to any server.
Yes. Use the rotate button to switch between landscape and portrait orientation. The preview area adjusts automatically.