WinUI

WinUI is a Windows-based user interface framework developed by Microsoft for building modern, native Windows applications. It provides a rich, extensible set of controls and styling aimed at delivering a consistent and Fluent-inspired user experience across devices and form factors.

WinUI originated with WinUI 2.x, which supplied updated UI controls for apps built on the Universal Windows Platform. With the introduction of the Windows App SDK (formerly Project Reunion), Microsoft released WinUI 3 as the current, fully native UI framework for Windows desktop apps and UWP alike. WinUI 3 decouples the UI layer from the OS and is delivered and versioned independently through NuGet as part of the Windows App SDK.

Developers build with XAML and languages such as C# or C++, targeting Windows 10 and Windows 11. WinUI is designed around MVVM, data binding, templating, and a comprehensive XAML control set, including typical elements like buttons, text boxes, lists, menus, navigation bars, and more. The framework emphasizes high-DPI rendering, accessibility, and Fluent Design aesthetics, with support for animations, styling, theming, and virtualization.

WinUI serves as the foundation for new Windows apps and can be used with desktop-style app lifecycles. It is not intended for non-Windows platforms. It is open source and receives ongoing maintenance and updates in tandem with Windows App SDK releases.

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