ViewPortX - Responsive Testing Workspace

The fastest visual responsive testing workspace for developers, designers, agencies, and clients.

ViewPortX – Responsive Website Testing Made Easy ViewPortX helps you test responsive websites faster by showing multiple screen sizes in one workspace. Instead of constantly resizing your browser or switching between devices, you can preview your website across mobile, tablet, laptop, and desktop layouts side by side. Whether you're building a website, checking a new design, or testing updates, ViewPortX makes responsive testing simple and efficient. Features View Multiple Devices Together Preview websites on mobile, tablet, laptop, and desktop screens. Compare different screen sizes side by side. Switch between Grid View and Focus View. Change between portrait and landscape orientation. Synchronized Scrolling Scroll one viewport and keep all other viewports in sync. Test responsive layouts more quickly. Check how pages behave across different screen sizes. Device Frames Display websites inside realistic device frames. Choose from popular phones, tablets, laptops, desktops, or a simple browser frame. Create clean previews for clients, presentations, or portfolios. Custom Screen Sizes Select from common device presets. Create your own custom width and height. Test specific responsive breakpoints for your project. Screenshots Capture high-quality screenshots of individual devices or the complete layout. Save screenshots for design reviews, testing, bug reports, or documentation. Projects and Workspaces Save your favorite layouts. Organize different websites into projects. Continue your work anytime without setting everything up again. Who Can Use ViewPortX? ViewPortX is useful for: Web Developers testing responsive layouts. UI/UX Designers reviewing designs on different screen sizes. QA Engineers checking responsive issues. Agencies and Freelancers presenting websites to clients. Fast and Privacy Friendly Works directly inside your browser. No server processing required. No unnecessary data collection. Fast and lightweight for everyday use. Getting Started Install the ViewPortX extension. Open any website. Click the ViewPortX extension icon. Start testing your website across multiple screen sizes instantly.