Responsive Design

Preview any website on 40+ devices. Compare responsive layouts with real device resolutions. Free for developers.

Responsive Design Checker lets you preview any website on 40+ real device resolutions instantly — right from your browser. FEATURES: • 52 real devices: iPhone 15, 15 Pro Max, SE, Galaxy S24, Pixel 8, iPad, Surface Pro, MacBook, Desktop 4K, and many more • Multi-preview: view your site on phone, tablet, and desktop side by side • Custom resolution: enter any width × height to test specific breakpoints • Device frames: toggle realistic device bezels for presentations and screenshots • Rotate: switch between portrait and landscape with one click • Screenshot: capture the current preview as PNG • Zoom controls: fit to screen, 1:1, zoom in/out • Keyboard shortcuts: R (rotate), S (screenshot), F (fit), +/- (zoom) • Dark interface designed for comfortable, distraction-free testing HOW IT WORKS: 1. Click the extension icon or enter any URL 2. Pick a device from the list (organized by category: iPhone, Android, Tablet, Desktop) 3. Your site loads in a real-size iframe — test responsive behavior instantly PERFECT FOR: • Web developers checking responsive breakpoints • UI/UX designers reviewing layouts across devices • QA testers verifying cross-device rendering • Freelancers presenting designs to clients 100% FREE — all features unlocked, no account required, no data collected. Privacy: Responsive Design Checker does not collect, store, or transmit any personal data. All previews run locally in your browser. No analytics, no tracking, no cookies.