Screen Resolution Simulator

Preview any website at different screen resolutions and device sizes. Test your responsive design without a physical device.

Zoom:1366×768px

Enter a URL and click Preview to simulate at 1366×768px

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Free Screen Resolution Simulator — Preview Your Website on Any Device

Responsive web design requires testing at dozens of screen sizes — but you cannot own every device. This free Screen Resolution Simulator lets you preview any website at any screen resolution by entering a URL and selecting a device preset or custom dimensions. See exactly how your website looks on a 375px iPhone SE, a 768px iPad, a 1280px laptop, or a 1920px desktop monitor — all from one tool.

Enter a URL and select from popular device presets (iPhone, Android phones, iPads, laptops, desktops) or enter custom pixel dimensions. The tool renders the page in an iframe at the selected viewport width so you can immediately see how your responsive CSS breakpoints behave at different sizes.

Testing at multiple resolutions is essential before launch and after major CSS changes. Broken mobile layouts — text cut off, buttons overlapping, navigation collapsed incorrectly, images wider than the viewport — are among the most common website issues reported by mobile users and negatively affect both user experience and Core Web Vitals scores.

Key Screen Sizes to Test

375px — Small mobile. iPhone SE, older Android phones. The minimum screen size for most modern mobile-first designs.

390px — Modern iPhone. iPhone 14/15 standard. The most common iPhone viewport width in 2024.

768px — Tablet. iPad portrait mode. Common CSS breakpoint where mobile layouts switch to tablet layouts.

1024px — Small laptop. iPad landscape, entry-level laptops. Navigation often switches from hamburger to full horizontal menu here.

1440px — Standard desktop. Common laptop/desktop resolution. Maximum content width for most designs (often capped at 1200–1400px with side margins).

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Frequently Asked Questions

What is it?

Previews any website at different screen sizes/resolutions to test responsive layouts without physical devices.

Why test resolutions?

60%+ of traffic is mobile. Broken layouts at small screens hurt UX and Core Web Vitals scores.

What sizes to test?

375px, 390px, 768px, 1024px, 1280px, 1440px, 1920px — covering phones through large desktops.

Is this free?

Yes. Completely free, no account needed.