Window Resizer Pro

Window Resizer Pro helps developers and designers test responsive layouts by quickly resizing the browser. Instead of dragging window edges and guessing the size, you can click a preset to instantly match specific device dimensions like phones, tablets, or desktop monitors. The extension lets you resize either the entire browser window or just the inner viewport. It comes with standard built-in sizes, but you can also create custom presets for any resolution your project needs and easily switch between portrait and landscape modes while testing.