Screen Resolution Simulator

Preview a site at different resolutions

A website looks genuinely different on different screen sizes, and testing across them is essential for a design that works everywhere. This tool simulates how a website looks at a range of screen resolutions, so you can check your responsive design against the phones, tablets and monitors your visitors actually use before they find the problems.

Why testing resolutions matters

A responsive site changes its layout at different widths, and a design that looks perfect on your own screen may well break badly on a small phone, an awkward tablet width, or a very large monitor. Testing systematically across resolutions reveals exactly where the layout falls apart, text that overflows its container, elements that overlap each other, a navigation menu that collapses wrongly, while you still have time to fix it cleanly. Simulating the common resolutions lets you check the design against the real range of devices visitors bring, which is far more reliable than the tempting but dangerous assumption that it works everywhere simply because it happens to work on the screen in front of you.

Check every size

It runs entirely in your browser, so nothing you paste is uploaded, which matters when the input is your own code, configuration or security-sensitive data.

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