Fluent Cleaner is a Windows cleaning tool that removes temporary files, browser caches, obsolete registry entries, and residual application data. It uses a fast parser for the winapp2.ini format and operates without installation. The WinUI3 interface cleans the operating system, Microsoft Edge, other browsers, multimedia applications, Windows utilities, .NET Framework, DirectX, Microsoft Store apps, and installed games. It displays freed space after each cleaning session and warns when browsers are still running before deleting data.