ocornut/imgui

What is it?

Key features

• 01Immediate-mode API where UI is declared in code each frame, with no retained widget state to sync
• 02Outputs vertex buffers and batched draw calls, so the renderer is independent of the library
• 03Core is a few self-contained source files with no external dependencies
• 04Official backends for multiple graphics APIs and platforms, including Win32, GLFW, SDL and Android
• 05Built-in demo window showing a wide range of widgets, plots and layout options

Use cases

• Adding debug panels or profiling views to a game engine or real-time 3D application
• Building content-creation or data inspection tools that need quick iteration
• Creating an in-app tweaking UI for variables on consoles or embedded systems with non-standard OS features

Quick start

1. 1

   Add the core imgui*.cpp and imgui*.h files from the repository root to your project

2. 2

   Pick the backends from the backends/ folder that match your graphics API and platform

3. 3

   Call ImGui::ShowDemoWindow() to see example features, with source in imgui_demo.cpp

Things to know

• !Full internationalization is not supported, including right-to-left and bidirectional text.
• !Accessibility features are not supported.
• !It is designed for debug, tool and game-engine interfaces rather than average end-user UI.

Topics

FAQ

What is imgui?

Dear ImGui is a bloat-free, dependency-light immediate-mode GUI library for C++ aimed at debug, tool and game-engine interfaces. Dear ImGui is a graphical user interface library for C++ that uses the immediate-mode paradigm. Instead of building and retaining a widget tree, the application calls functions such as Button or SliderFloat each frame, and the library returns whether the user interacted with them. The core is a few platform-agnostic source files that can be added directly to an existing project without a special build process.

Is imgui free to use? What license does it have?

imgui is open source under the MIT license. Check the license terms before using it in commercial products.

Is imgui still maintained?

Actively maintained. The last commit to imgui was on Oct 16, 2026.

What can I use imgui for?

Adding debug panels or profiling views to a game engine or real-time 3D application Building content-creation or data inspection tools that need quick iteration Creating an in-app tweaking UI for variables on consoles or embedded systems with non-standard OS features

How do I install imgui?

Add the core imgui*.cpp and imgui*.h files from the repository root to your project Pick the backends from the backends/ folder that match your graphics API and platform Call ImGui::ShowDemoWindow() to see example features, with source in imgui_demo.cpp

Where can I get imgui?

The source code and installation instructions are on GitHub: https://github.com/ocornut/imgui