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A quick and easy way to test your website design in multiple screen widths
240 x 320 (small phone) 
320 x 480 (iPhone)
480 x 640 (small tablet)
768 x 1024 (iPad - Portrait)
1024 x 768 (iPad - Landscape)
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Responsive screen sizes
Test your website on any screen size including desktops, tablets, televisions, and mobile phones.
Every modern web designer should be familiar with the concepts of responsive web design – how to make your sites perfectly render on any platform or screen size they appear on. Check that your web site works on a responsive template.
The tool adjusts all its elements according to the sizes of the screens for various devices when testing the responsive template. Verify all screen sizes to properly test your template with proper accuracy.
Note: The content width may not be pixel perfect - I have added 15px to the iframes to cater for the scrollbars.
Test your responsive websites using Responsive Design Testing tool. It is a great tool that can help you know whether the design of your site is responsive or not.
It comes with a simple and intuitive user interface that lets you enter the URL of your site into the given address at the top of this page to test the responsiveness of a particular web page.
Computers are useless. They can only give you answers.