All Modules

Qt Essentials

Qt Essentials define the foundation of Qt on all platforms. They are available on all supported development platforms and on the tested target platforms. Except the testing modules, which will remain source compatible, these modules will remain source and binary compatible throughout Qt 6.

Essential modules are general and useful for a majority of Qt applications. A module that is used for a special purpose is considered an add-on module even if it is available on all supported platforms.

The following table lists the Qt essentials:

Qt CoreCore non-graphical classes used by other modules.
Qt D-BusClasses for inter-process communication over the D-Bus protocol.
Qt GUIBase classes for graphical user interface (GUI) components.
Qt NetworkClasses to make network programming easier and more portable.
Qt QMLClasses for QML and JavaScript languages.
Qt QuickA declarative framework for building highly dynamic applications with custom user interfaces.
Qt Quick ControlsProvides lightweight QML types for creating performant user interfaces for desktop, embedded, and mobile devices. These types employ a simple styling architecture and are very efficient.
Qt Quick LayoutsLayouts are items that are used to arrange Qt Quick 2 based items in the user interface.
Qt Quick TestA unit test framework for QML applications, where the test cases are written as JavaScript functions.

Note: The binary compatibility guarantee does not apply to Qt Quick Test. However, it will remain source compatible.

Qt TestClasses for unit testing Qt applications and libraries.

Note: The binary compatibility guarantee does not apply to Qt Test. However, it will remain source compatible.

Qt WidgetsClasses to extend Qt GUI with C++ widgets.

Qt Add-Ons

Qt Add-On modules bring additional value for specific purposes. These modules may only be available on some development platform. Many add-on modules are either feature-complete and exist for backwards compatibility, or are only applicable to certain platforms. Each add-on module specifies its compatibility promise separately.

The Qt installers include the option of downloading the add-ons. For more information, visit the Getting Started with Qt page.

The following table lists the Qt add-ons:

ModuleDevelopment PlatformsTarget PlatformsDescription
Qt 3DAllAllFunctionality for near-realtime simulation systems with support for 2D and 3D rendering.
Qt 5 Core Compatibility APIsAllAllQt Core APIs that were in Qt 5 but not Qt 6.
Qt ConcurrentAllAllClasses for writing multi-threaded programs without using low-level threading primitives.
Qt HelpAllAllClasses for integrating documentation into applications.
Qt Image FormatsAllAllPlugins for additional image formats: TIFF, MNG, TGA, WBMP.
Qt OpenGLAllAllC++ classes that make it easy to use OpenGL in Qt applications. A separate library of Qt OpenGL Widgets C++ Classes provides a widget for rendering OpenGL graphics.
Qt Print SupportAllAllClasses to make printing easier and more portable.
Qt Quick 3DAllAllProvides a high-level API for creating 3D content or UIs based on Qt Quick.
Qt Quick TimelineAllAllEnables keyframe-based animations and parameterization.
Qt Quick WidgetsAllAllProvides a C++ widget class for displaying a Qt Quick user interface.
Qt Shader ToolsAllAllProvides tools for the cross-platform Qt shader pipeline. These enable processing graphics and compute shaders to make them usable for Qt Quick and other components in the Qt ecosystem.
Qt SQLAllAllClasses for database integration using SQL.
Qt SVGAllAllClasses for displaying the contents of SVG files. Supports a subset of the SVG 1.2 Tiny standard. A separate library of Qt SVG Widgets C++ Classes provides support for rendering SVG files in a widget UI.
Qt UI ToolsAllAllClasses for loading QWidget based forms created in Qt Designer dynamically, at runtime.
Qt XMLAllAllHandling of XML in a Document Object Model (DOM) API.

Add-ons available under Commercial Licenses, or GNU General Public License v3

Qt Network AuthorizationAllAllProvides support for OAuth-based authorization to online services.
Qt Wayland CompositorLinuxLinux and Boot to Qt targets.Provides a framework to develop a Wayland compositor.

Where to Go from Here

We invite you to explore the rest of Qt. We prepared overviews which help you decide which APIs to use and our examples demonstrate how to use our API.

© 2021 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners. The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners.