Licenses Used in Qt

Qt contains some code that is not provided under the GNU Lesser General Public License (LGPL) or the Qt Commercial License, but rather under specific licenses from the original authors.

The Qt Company gratefully acknowledges these and other contributions to Qt. We recommend that programs that use Qt also acknowledge these contributions, and quote these license statements in an appendix to the documentation.

Note: You only need to comply with (and acknowledge) the licenses of the third-party components that you are using with your application. Click the name of the component to see the licensing details.

Third-party Licenses

The following table lists parts (modules) of Qt 6.4.3 that incorporate code licensed under third-party open-source licenses:

Qt 3D

Dear ImGui - ProggyClean.ttf	MIT License
Dear ImGui - stb	MIT License or Public Domain
Dear ImGui, version v1.66b	MIT License

Qt 5 Core Compatibility APIs

Text Codec: EUC-JP	BSD 2-clause "Simplified" License
Text Codec: EUC-KR	BSD 2-clause "Simplified" License
Text Codec: GBK	BSD 2-clause "Simplified" License
Text Codec: ISO 2022-JP (JIS)	BSD 2-clause "Simplified" License
Text Codec: Shift-JIS	BSD 2-clause "Simplified" License
Text Codec: TSCII	BSD 2-clause "Simplified" License
Text Codecs: Big5, Big5-HKSCS	BSD 2-clause "Simplified" License

Qt Bluetooth

BlueZ

GNU General Public License v2.0 only (This does not force user code to be GPL'ed. For more info see details.)

Qt Core

BLAKE2 (reference implementation), version 54f4faa4c16ea34bcd59d16e8da46a64b259fc07	Creative Commons Zero v1.0 Universal or Apache License 2.0
Data Compression Library (zlib), version 1.2.13	Zlib License
Easing Equations by Robert Penner	BSD 3-clause "New" or "Revised" License
Efficient Binary-Decimal and Decimal-Binary Conversion Routines for IEEE Doubles, version 3.2.0+e634f265db5d296bd7a780f9813d6b8573f5bd90	BSD 3-clause "New" or "Revised" License
KWin, version 5.13.4	BSD-3-Clause
KWin, version 5.13.4	BSD-3-Clause
KWin, version 5.13.4	BSD-3-Clause
MD4	Public Domain
MD5	Public Domain
PCRE2 - Stack-less Just-In-Time Compiler, version 10.42	BSD 2-clause "Simplified" License
PCRE2, version 10.42	BSD 3-clause "New" or "Revised" License
QEventDispatcher on macOS	BSD 3-clause "New" or "Revised" License
Secure Hash Algorithm SHA-1	Public Domain
Secure Hash Algorithm SHA-3 - Keccak, version 3.2	Creative Commons Zero v1.0 Universal
Secure Hash Algorithm SHA-3 - brg_endian, version https://github.com/BrianGladman/sha/ commit 4b9e13ead2c5b5e41ca27c65de4dd69ae0bac228	BSD 2-clause "Simplified" License
Secure Hash Algorithms SHA-384 and SHA-512	BSD 3-clause "New" or "Revised" License
SipHash Algorithm	Creative Commons Zero v1.0 Universal
TinyCBOR, version 0.6.0	MIT License
Unicode Character Database (UCD), version 28	Unicode License Agreement - Data Files and Software (2016)
Unicode Common Locale Data Repository (CLDR), version v41	Unicode License Agreement - Data Files and Software (2016)
extra-cmake-modules, version 5.84.0	BSD-3-Clause
extra-cmake-modules, version 5.84.0	BSD-3-Clause
extra-cmake-modules, version 5.84.0	BSD-3-Clause
forkfd	MIT License

Qt D-Bus

libdus-1 headers, version dbus-1.13.12

Academic Free License v2.1, or GNU General Public License v2.0 or later

Qt GUI

Adobe Glyph List For New Fonts, version 1.7	BSD 3-Clause "New" or "Revised" License
Anti-aliasing rasterizer from FreeType 2	Freetype Project License or GNU General Public License v2.0 only
Bitstream Vera Font, version 1.10	Bitstream Vera Font License
Cocoa Platform Plugin	BSD 3-clause "New" or "Revised" License
DejaVu Fonts, version 2.37	Bitstream Vera Font License
Freetype 2 - Bitmap Distribution Format (BDF) support	MIT License
Freetype 2 - Portable Compiled Format (PCF) support	MIT License and MIT Open Group variant
Freetype 2 - zlib	Zlib License
Freetype 2, version 2.13.0	Freetype Project License or GNU General Public License v2.0 only
HarfBuzz-NG, version 7.0.1	MIT License
IAccessible2 IDL Specification, version 1.3.0	BSD 3-clause "New" or "Revised" License
LibJPEG-turbo, version 2.1.5	Independent JPEG Group License and BSD 3-Clause "New" or "Revised" License and zlib License
LibPNG, version 1.6.39	Libpng License and PNG Reference Library version 2
MD4C, version 0.4.8	MIT License
Native Style for Android	Apache License 2.0
OpenGL ES 2 Headers, version Revision 27673	MIT License
OpenGL Headers, version Revision 27684	MIT License
Pixman, version 0.17.12	MIT License
Smooth Scaling Algorithm	BSD 2-clause "Simplified" License and Imlib2 License
Vulkan API Registry, version 1.2.166	Apache License 2.0 or MIT License
Vulkan Memory Allocator, version 2.3.0	MIT License
WebGradients	MIT License
Wintab API	LCS-Telegraphics License
X Server helper	X11 License and Historical Permission Notice and Disclaimer
XCB-XInput	MIT License
sRGB color profile icc file	International Color Consortium License

Qt Image Formats

TIFF Software Distribution (libtiff), version 4.5.0	Libtiff License
WebP (libwebp), version 1.3.0	BSD 3-clause "New" or "Revised" License

Qt Network

The Public Suffix List, version d17a65633b0286833727ef21e897a22564695ef5, fetched on 2022-05-23	Mozilla Public License 2.0
libpsl - C library to handle the Public Suffix List, version 664f3dc85259ec65e30248a61fa1c45b7b0e4c3f	BSD 3-clause "New" or "Revised" License

Qt OPC UA

Open62541, version 1.1

Mozilla Public License 2.0 and Creative Commons Zero v1.0 Universal and Creative Commons Attribution Non Commercial Share Alike 4.0 International and BSD 3-Clause "New" or "Revised" License and Apache License 2.0 and MIT License

Qt Positioning

Clip2Tri Polygon Triangulation Library	MIT License
Clipper Polygon Clipping Library, version 6.4.2	Boost Software License 1.0
Poly2Tri Polygon Triangulation Library	BSD 3-clause "New" or "Revised" License

Qt QML

JavaScriptCore Macro Assembler

BSD 2-clause "Simplified" License

Qt Quick 3D

Intel Embree, version 3.13.3	Apache License 2.0
Open Asset Import Library, version 5.2.3	BSD 3-clause "New" or "Revised" Licensee
ProceduralSky	MIT License
Tiny OpenEXR, version v1.0.1	BSD 3-clause "New" or "Revised" License
xatlas, version 16ace528acd2cf1f16a7c0dde99c42c486488dbe	MIT License

Qt Quick 3D Physics

NVIDIA PhysX SDK, version PhysX_4.1.2.29882248

BSD 3-Clause "New" or "Revised" License

Qt Quick Controls

Shadow values from Angular Material

MIT License

Qt SQL

SQLite, version 3.41.0

Public Domain

Qt SVG

XSVG	Historical Permission Notice and Disclaimer - sell variant

Qt Spatial Audio

Eigen, version 3.4.0	Mozilla Public License 2.0 and BSD 3-Clause "New" or "Revised" License
Resonance Audio, version e225aedb5ec76ca6a0fe7079c0b84dbcbb490553	Apache License 2.0
pfft, version 7c3b5a7dc510a0f513b9c5b6dc5b56f7aeeda422	BSD 3-Clause "New" or "Revised" License

Qt Test

Catch2, version 2.13.10	Boost Software License 1.0
Cycle	MIT License
Linux Performance Events, version 3.7	GNU General Public License v2.0 only with Linux Syscall Note
Valgrind, version 3.14.0	BSD 4-clause "Original" or "Old" License

Qt Virtual Keyboard

OpenWnn	Apache License 2.0
PinyinIME	Apache License 2.0
Traditional Chinese IME (tcime)	Apache License 2.0 and BSD 3-clause "New" or "Revised" License

Qt Wayland Compositor

Presentation Time Protocol, version 1	MIT License
Wayland EGLStream Controller Protocol, version 1.1.1	MIT License
Wayland Fullscreen Shell Protocol, version unstable v1	MIT License
Wayland IVI Extension Protocol, version 1.9.1	MIT License
Wayland Linux Dmabuf Unstable V1 Protocol, version unstable v1, version 3	MIT License
Wayland Pointer Gestures Protocol, version unstable v1, version 2	MIT License
Wayland Primary Selection Protocol, version 1	MIT License
Wayland Protocol, version 1.19.0	MIT License
Wayland Scaler Protocol, version 2	MIT License
Wayland Tablet Protocol, version unstable v2, version 1	MIT License
Wayland Text Input Protocol v1, version unstable v1	MIT License
Wayland Text Input Protocol v2, version unstable v2	HPND License
Wayland Text Input Protocol, version unstable v4, WIP	HPND License
Wayland Viewporter Protocol, version 1	MIT License
Wayland XDG Output Protocol, version unstable v1, version 3	MIT License
Wayland XDG Shell Protocol, version 1.18	MIT License
Wayland xdg-activation Protocol, version unstable v1, version 1	MIT License
Wayland xdg-decoration Protocol, version unstable v1, version 1	MIT License

Qt WebEngine

2-dim General Purpose FFT (Fast Fourier/Cosine/Sine Transform) Package	Custom
ARCore SDK	Apache 2.0
ARCore SDK client library for Chrome	Apache 2.0
ARM_NEON_2_x86_SSE	Custom
AXE-CORE Accessibility Audit	MPL 2.0
Abseil	Apache 2.0
Acorn, a tiny, fast JavaScript parser written in JavaScript.	MIT
Acorn-loose	MIT
Alliance for Open Media Video Codec	BSD
Almost Native Graphics Layer Engine	BSD
Android Explicit Synchronization	Apache 2.0
Blackmagic DeckLink SDK - Mac	BSL (v 1.0)
BoringSSL	BSDish
Breakpad, An open-source multi-platform crash reporting system	New BSD, Apple PSL 2.0 and Apache 2.0
Brotli	MIT
C++ port of zxcvbn, an advanced password strength estimation library.	MIT
CRC32C	New BSD
CastCore Publics	Apache 2.0
Chromium License	BSD
Chromium OS system API	BSD
CityHash	MIT
Closure compiler	Apache 2.0
Cocoa extension code from Camino	MPL 1.1/GPL 2.0/LGPL 2.1
CodeMirror 5	MIT
CodeMirror 6	MIT
Compact Encoding Detection	Apache 2.0
Compact Language Detector v3	Apache 2.0
Crashpad	Apache 2.0
Darwin	Apple Public Source License 2.0
Dawn	Apache 2.0
Devtools-Frontend	BSD
EasyList	Creative Commons Attribution-ShareAlike 3.0 Unported
Eigen	MPL 2
Emoji Segmenter	Apache 2.0
Expat XML Parser	MIT
FP16	MIT
FarmHash	Custom
Fiat-Crypto: Synthesizing Correct-by-Construction Code for Cryptographic Primitives	MIT
FideltyFX Single Pass Downsampler	MIT
FlatBuffers	Apache 2.0
FreeType	Custom license "inspired by the BSD, Artistic, and IJG (Independent
Fuse.js	Apache License, Version 2.0
GVR Android SDK	Apache 2.0
GVR Keyboard	Apache 2.0
GifPlayer Animated GIF Library	Apache License 2.0
Google Closure Library	Apache 2.0
Google Double Conversion	BSD
Headers for the Windows 10 WebAuthn API (webauthn.dll)	MIT
Highway: C++ library for SIMD	Apache 2.0
IAccessible2 COM interfaces for accessibility	BSD
ISimpleDOM COM interfaces for accessibility	MPL 1.1/GPL 2.0/LGPL 2.1
JPEG XL image decoder library	BSD 3-Clause
Jinja2 Python Template Engine	BSD 3-Clause
Khronos Vulkan Tools Components	Apache 2.0
Khronos Vulkan Validation Layers Components	Apache 2.0
Khronos header files	MIT/X11, SGI Free Software License B
Khronos reference front-end for GLSL and ESSL	MIT
LZMA SDK	Public Domain
LevelDB: A Fast Persistent Key-Value Store	New BSD
Lighthouse	Apache License 2.0
Lighthouse i18n.js	Apache License 2.0
Lit-HTML	BSD-3
Lottie Web	MIT
MalDocA source for extracting and analyzing features from Office documents.	Apache 2.0
Marked	LICENSE
Material Design Icons	Apache 2.0
Material Web Components	Apache 2.0
Metrics Protos	BSD
Mozilla Windows Cert code	MPL 2
Nearby Connections Library	Apache 2.0
Netscape Portable Runtime (NSPR)	MPL 1.1/GPL 2.0/LGPL 2.1
Netwide Assembler	2-Clause BSD
Network Security Services (NSS)	MPL 2
OTS (OpenType Sanitizer)	BSD
One Euro Filter	BSD
Open Screen Protocol Library	BSD
OpenH264	2-Clause BSD
PDFium	BSD
PFFFT: a pretty fast FFT.	BSD-like
PLY (Python Lex-Yacc)	BSD
PSM (Private Set Membership) client side	Apache Version 2.0
Paul Hsieh's SuperFastHash	BSD
Perfetto	Apache2
Polymer	BSD
Private Join and Compute subset	Apache 2.0
Protocol Buffers	BSD
Puppeteer	Apache-2.0
QUICHE	BSD
Quick Color Management System	MIT
Recurrent neural network for audio noise reduction	BSD 3-Clause
SMHasher	MIT, Public Domain
SPIR-V Headers	MIT
SPIR-V Tools	Apache 2.0
SPIRV-Cross	Apache 2.0
Secure Message	Apache 2.0
Setupdesign	Apache 2.0
Simple Homomorphic Encryption Library with Lattices	Apache Version 2.0
Skia	BSD
Snappy: A fast compressor/decompressor	New BSD
Speech Dispatcher	GPL (v2 or later)
Strongtalk	BSD
Sudden Motion Sensor library	University of Illinois/NCSA Open Source License
SwiftShader	Apache 2.0 and compatible licenses
TensorFlow Lite	Apache 2.0
TensorFlow Lite Support	Apache 2.0
TensorFlow Text	Apache 2.0
Text Fragments Polyfill	Apache 2.0
The Chromium Project	BSD 3-clause "New" or "Revised" License
The Diff Match and Patch libraries offer robust algorithms to perform the operations required for synchronizing plain text.	Apache License 2.0
The Incremental Distributed Point Functions library	Apache 2.0
The USB ID Repository	BSD
The ruy matrix multiplication library	Apache 2
UKey2	Apache 2.0
URI Template Parser	Apache 2.0
URL Pattern Library	MIT
Unicode Common Locale Data Repository	MIT-like
V8 JavaScript Engine	BSD
V8 fork of fdlibm	Fdlibm license
Vulkan API headers	Apache 2.0
Vulkan Deps	BSD
Vulkan Loader Components	Apache 2.0
VulkanMemoryAllocator	MIT
Wasmparser	Apache
Web Animations JS	Apache 2.0
WebKit	BSD and LGPL v2 and LGPL v2.1
WebM container parser and writer.	BSD
WebP image encoder/decoder	BSD
WebRTC	BSD
Weston - reference Wayland compositor	MIT
Windows Template Library (WTL)	Microsoft Permissive License
Wuffs (Wrangling Untrusted File Formats Safely)	Apache 2.0
bspatch	BSD 2-Clause License
d3	BSD 3-Clause
dav1d is an AV1 decoder :)	2-Clause BSD
dom-distiller-js	BSD
dynamic annotations	BSD
emoji-metadata	Apache 2.0
fdlibm	Freely Distributable
ffmpeg	LGPL 2.1
flac	BSD
flex	BSD
fontconfig	MIT
gemmlowp	Apache 2
google-glog's symbolization library	BSD
google-jstemplate	Apache 2.0
harfbuzz-ng	MIT
hunspell	MPL 1.1/GPL 2.0/LGPL 2.1
hyphenation-patterns	MIT, MPL 1.1/GPL 2.0/LGPL 2.1, GNU Lesser Public License, Unicode License, Unicode Data License, custom notice license, custom permissive license
iccjpeg	Custom license
icu	MIT
inspector protocol	BSD
intl-messageformat	New BSD
ipcz	BSD
jsoncpp	MIT
libaddressinput	Apache 2.0
libavif - Library for encoding and decoding .avif files	2-Clause BSD
libbrlapi	LGPL 2.1
libevent	BSD
libgav1	Apache 2.0
libgif codec for Skia	MPL-1.1/GPL-2.0/LGPL-2.1 + BSD-3-Clause + BSD-2-Clause
libipp	BSD
libjingle XMPP and xmllite libraries	BSD
libjpeg-turbo	Custom license
libpng	Libpng license
libprotobuf-mutator	Apache 2.0
libsecret	LGPL 2.1
libsrtp	3-clause BSD
libudev	LGPL 2.1
libusbx	LGPL 2.1
libutf	MIT License
libvpx	BSD
libx11	MIT
libxcb-keysyms	MIT
libxml	MIT
libxslt	MIT
libyuv	BSD
libzip	Custom
linux-syscall-support	BSD
mesa_headers	MIT and SGI Free Software B License Version 2.0
minigbm	BSD
modp base64 decoder	BSD
nmoinvaz/minizip	Custom license
opus	BSD
pprof	Apache 2.0
pyjson5	Apache 2.0
pywebsocket3	New BSD
re2 - an efficient, principled regular expression library	BSD 3-Clause
rjsmin	Apache 2.0
simplejson	MIT
sqlite	Public domain
test_fonts	SIL OPEN FONT LICENSE, GPL v2, Bitstream Vera Fonts Copyright
url_parse	BSD and MPL 1.1/GPL 2.0/LGPL 2.1
v4l-utils	LGPL 2.1
valgrind	BSD
woff2	MIT
x11proto	MIT
xdg-mime	Academic Free License version 2.0 or LGPL v2
xdg-user-dirs	MIT
xdg-utils	MIT
xxHash	BSD
zlib	Custom license

Shader Tools

SPIRV-Cross, version d137abeef57b2f3fdbdab0ad5590fe99a44ba546	Apache License 2.0 and Khronos License
glslang, version 11.1.0	BSD 3-Clause "New" or "Revised" License, and Khronos License, and Apache License 2.0, and GNU General Public License v3.0 or later with Bison exception 2.2, and NVIDIA 2002 License

Additional Information

The following table lists related documents, such as information about Trademarks and other licenses used in parts of Qt.

Android GNU C++ Run-time Licensing	Provides additional information about the licensing of run-time dependencies of Qt for Android
LLVM Attribution	University of Illinois/NCSA Open Source License, BSD licenses
License Changes	Information about changes of licenses in Qt and Third Party Modules
Macros for Building with CMake	BSD 3-clause "New" or "Revised" License
Mesa llvmpipe	MIT License
Notes about PDF Licensing	Details of restrictions on the use of PDF-related trademarks
The QtEntryPoint Library	Commercial and BSD 3-clause "New" or "Revised" License.
Trademarks	Information about trademarks owned by The Qt Company.

© 2023 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.