This is a modern, SEO-optimized HTML document for a responsive website testing tool. It includes a complete set of meta tags for better search engine visibility and social sharing, along with a clean, contemporary interface. ```html

Responsive Testing Tool 100+ devices

Preview any website on mobile, tablet, desktop & TV — instant resize, rotate & scroll

Custom ×

1024 × 600 Desktop

Is your website truly device‑friendly?

Test any URL across 100+ real device presets. See exactly how your site looks on iPhone, iPad, Samsung Galaxy, Nexus, Microsoft Surface, and even 4K/8K televisions.

Use the custom size panel to enter exact viewport dimensions, rotate orientation, or toggle scrolling. Bookmark your favorite view for quick reference.

Perfect for developers, designers, and content creators who need a fast, no‑install responsive preview.

Device friendly?
Preview on all screens

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