Responsive Checker - Mobile Simulator Pro

Responsive check & mobile friendly test on 55+ device simulators. Side-by-side preview, screenshots & custom viewports.

Smartphone and tablet simulator on your computer with 55+ device models to check how your website looks on mobile in seconds. 🚀 Verify your responsive design, preview your site the way visitors see it, create client-ready previews, and save hours of manual testing. A fast, lightweight testing tool built for developers, designers, and agencies — with zero data collection. 📱 55+ PRE-CONFIGURED DEVICES - Modern and older smartphones with accurate viewport sizes - Popular tablets in multiple screen sizes - Special profiles: smartwatch, laptop, desktop, kiosk, and foldable 🔥 MAIN FEATURES - Multi-device comparison — view up to 6 devices side-by-side simultaneously, so you can spot breakpoint issues without switching between viewports - Custom devices — create and save your own screen resolutions for any project requirement - Accurate viewports — every preset uses real CSS viewport dimensions and device pixel ratios - One-click screenshots — capture device previews as PNG, saved straight to your Downloads folder - Instant rotation — flip every open device between portrait and landscape with a single click - Smart zoom — scale the workspace from 30% to 150% to fit more devices on screen - Light theme by default, with an optional dark mode 🎁 ALSO INCLUDED - Realistic device frames with notch, island, and punch-hole rendering - Reload all devices at once - Your settings and custom devices are remembered between sessions - Works on any website — just enter a URL ⚡ WHY USERS CHOOSE THIS EXTENSION - 100% free — no account, no sign-up, no limits - Zero data collection — everything runs locally in your browser - Lightweight — no background processes slowing Chrome down - Search engines rank mobile-friendly sites higher. Check your pages before every launch and catch layout issues before your visitors do. 🔒 PRIVACY FIRST This extension collects no data whatsoever. No analytics, no tracking, no external servers. Your URLs, screenshots, and settings never leave your device. (Note: A simulator reproduces mobile viewports with high accuracy for day-to-day development, but does not replace final validation on a real physical device.)