Test Your Website's Responsiveness in Real Time
Free tool to test your website's responsive design.
Enter a URL above and choose from 30+ devices in the sidebar to start validating your mobile experience.
+35 Devices
Smartphones, Tablets and Desktops.
Rotate Screen
Test Portrait (Vertical) and Landscape (Horizontal).
Smart Zoom
Adjust the view without losing pixel fidelity.
Custom Resolution
Set width and height for breakpoint testing.
How it works: Test your website in 3 simple steps
Visualize your website in real time on mobile devices, tablets, desktops and custom resolutions, ensuring a flawless experience and perfect appearance on any screen.
Paste your project URL
Enter the address (e.g.: https://cooder.com.br) in the search bar and click load.
Select the Device
Use our sidebar to switch between iPhone, Samsung Galaxy, iPads, MacBooks and even Smart TVs.
Analyze Design and Breakpoints
Check if elements like menus, images and texts are aligned. Use the 'Share Configuration' feature to send the test to your team.
Frequently Asked Questions about Website Responsiveness
Our tool has updated presets for iOS and Android, including the latest iPhone, Google Pixel and Xiaomi models, as well as Full HD laptops and 4K/8K monitors.
Yes, as long as the environment is accessible by the browser you are using to run the simulator.
Yes, the tool is 100% free for developers and designers looking to optimize the user experience (UX).
To test responsiveness, simply enter your project's URL in our tool. Our device simulator lets you instantly visualize how your page adapts to different screen widths, from iPhones and Androids to 4K monitors.
You can check responsiveness by observing whether content adjusts without the need for horizontal scrolling. Common problems include buttons too small to touch, overlapping text and images that don't resize. Our adaptability testing tool helps identify these layout errors visually.
The most recommended tool is a dedicated simulator like the one from Cooder Tecnologia. We offer an interface focused on free online tools to test web page responsiveness with more than 30 real device presets. You can also use the browser's DevTools (F12).
Responsive design is one of Google's main ranking factors (Mobile-First Indexing). Sites that don't offer good mobile usability lose positions in searches, resulting in less traffic and a lower conversion rate.
Yes. While our tool offers a quick visual analysis, Cooder Tecnologia offers a professional service for mobile usability evaluation, delivering detailed reports and technical fixes to ensure your site performs on any screen.
Cooder Tecnologia specializes in consulting and web development. If your site has loading failures or layout errors on mobile devices, our team is ready to optimize your code and improve your user experience.
Our device library is constantly updated. You can simulate from the latest iPhone models (14, 15, 16 Pro Max) to Samsung Galaxy, Google Pixel and Xiaomi devices, ensuring your site works on the most popular devices in the market.
Yes! We offer the screen rotation feature (landscape and portrait). This is essential for checking whether your mobile menu or data tables behave correctly when the user turns their phone sideways.
Absolutely. In addition to smartphones and tablets, our tool has presets for Smart TVs (4K and 8K) and custom desktop resolutions. This allows you to validate whether your site's images maintain quality on giant screens.
You can use our Custom Resolution feature. Simply type the width and height in pixels to create an exclusive test scenario for any CSS breakpoint.
Yes. The tool is ideal for Web App and SPA (Single Page Application) developers who need to validate the user interface (UI) and user experience (UX) on multiple devices without needing physical devices.
Need help with your website?
Cooder Tecnologia: Your web development partner in Brazil. If your responsiveness test flagged errors or you need a professional high-performance website, Cooder Tecnologia specializes in creating adaptable, SEO-optimized interfaces.
