Qt 5.15
Licenses Used in Qt
Qt 5.15.8 Reference Documentation

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 5.15.8 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
Open Asset Import Library, version 5.0.1	BSD 3-clause "New" or "Revised" Licensee

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

Data Compression Library (zlib), version 1.2.11	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 3.1.5	BSD 3-clause "New" or "Revised" License
FreeBSD strtoll and strtoull, version 18b29f3fb8abee5d57ed8f4a44f806bec7e0eeff	BSD 3-clause "New" or "Revised" License
MD4	Public Domain
MD5	Public Domain
PCRE2 - Stack-less Just-In-Time Compiler, version 10.39	BSD 2-clause "Simplified" License
PCRE2, version 10.39	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
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
The Public Suffix List, version d4e247a71d1b6da08dad906b098c818493166fcc, fetched on 2021-06-11	Mozilla Public License 2.0
TinyCBOR, version 0.6+patches	MIT License
Unicode Character Database (UCD), version 26	Unicode License Agreement - Data Files and Software (2016)
Unicode Common Locale Data Repository (CLDR), version v39	Unicode License Agreement - Data Files and Software (2016)
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

ANGLE Library, version chromium/3280	BSD 3-clause "New" or "Revised" License
ANGLE: Array Bounds Clamper for WebKit	BSD 2-clause "Simplified" License
ANGLE: Khronos Headers	MIT License
ANGLE: Murmurhash	Public Domain
ANGLE: Systeminfo	BSD 2-clause "Simplified" License
ANGLE: trace_event	BSD 3-clause "New" or "Revised" License
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
Freetype 2 - zlib	Zlib License
Freetype 2, version 2.10.4	Freetype Project License or GNU General Public License v2.0 only
HarfBuzz	MIT License
HarfBuzz-NG, version 1.7.4	MIT License
LibJPEG-turbo, version 2.1.1	Independent JPEG Group License and BSD 3-Clause "New" or "Revised" License and zlib License
LibPNG, version 1.6.37	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 1.0.39	MIT License
Vulkan Memory Allocator, version 2.2.0	MIT License
WebGradients	MIT 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 Location

Boost, version 1.65.1	Boost Software License 1.0
CSS Color Parser	MIT License
Clip2Tri Polygon Triangulation Library	MIT License
Clipper Polygon Clipping Library, version 6.4.0	Boost Software License 1.0
Earcut Polygon Triangulation Library	ISC License
Earcut, version 0.12.4	ISC License
Mapbox GL Native	BSD 2-clause "Simplified" License and zlib License
Optional	Boost Software License 1.0
Poly2Tri Polygon Triangulation Library	BSD 3-clause "New" or "Revised" License
RapidJSON, version 1.1.0	MIT License
Vector Tile Library, version 1.0.2	ISC License
Wagyu Geometry Processing Library, version 0.4.3	MIT License
cURL Parse Date	MIT License
geojson-cpp, version 0.4.2	ISC License
geojson-vt-cpp, version 6.5.1	ISC License
geometry.hpp, version 0.9.3	ISC License
geosimplify-js polyline simplification library	Geosimplify-js License
kdbush.hpp, version 0.1.1-1	ISC License
nunicode, version 1.8	MIT License
polylabel, version 1.0.3	ISC License
protozero, version 1.5.2	BSD 2-clause "Simplified" License
shelf-pack-cpp, version 2.1.1	ISC License
supercluster.hpp, version 0.2.2	ISC License
tao_tuple, version 28626e99	MIT License
unique_resource, version cba309e	Boost Software License 1.0
variant, version 1.1.4	BSD 3-clause "New" or "Revised" License

Qt QML

JavaScriptCore Macro Assembler

BSD 2-clause "Simplified" License

Qt Quick Controls

Shadow values from Angular Material

MIT License

Qt SVG

XSVG	Historical Permission Notice and Disclaimer - sell variant

Qt Script

JavaScriptCore, version Snapshot from 2011-01-27

GNU Library General Public License v2 or later

Qt Test

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 Wayland Compositor

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 Primary Selection Protocol, version 1	MIT License
Wayland Protocol, version 1.16.0	MIT License
Wayland Scaler Protocol, version 2	MIT License
Wayland Tablet Protocol, version unstable v2, version 1	MIT License
Wayland Text Input Protocol, version unstable v2	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-decoration Protocol, version unstable v1, version 1	MIT License

Qt WebEngine

ANGLE array bounds clamper from WebKit	BSD
ARCore SDK	Apache 2.0
ARCore SDK client library for Chrome	Apache 2.0
AXE-CORE Accessibility Audit	MPL 2.0
Abseil	Apache 2.0
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
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
Compact Encoding Detection	Apache 2.0
Compact Language Detector v3	Apache 2.0
Crashpad	Apache 2.0
Dawn	Apache 2.0
Emoji Segmenter	Apache 2.0
Expat XML Parser	MIT
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
Google Ink	Apache 2.0
Headers for the Windows 10 WebAuthn API (webauthn.dll)	MIT
IAccessible2 COM interfaces for accessibility	BSD
ISimpleDOM COM interfaces for accessibility	MPL 1.1/GPL 2.0/LGPL 2.1
Jinja2 Python Template Engine	BSD 3-Clause
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
Lottie Web	MIT
Material Design Icons	Apache 2.0
Metrics Protos	BSD
NVidia Control X Extension Library	MIT
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
Oculus SDK for Windows	By exception only
One Euro Filter	BSD
Open Screen Protocol Library	BSD
OpenCV	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
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
Schema.org is a collaborative, community activity with a mission to	Creative Commons Attribution-ShareAlike 3.0 Unported
Secure Message	Apache 2.0
Shaderc	Apache 2.0
Shaka Player	Apache 2.0
Simple Homomorphic Encryption Library with Lattices	Apache Version 2.0
Skia	BSD
Snappy: A fast compressor/decompressor	New BSD
Strongtalk	BSD
Sudden Motion Sensor library	University of Illinois/NCSA Open Source License
SwiftShader	Apache 2.0 and compatible licenses
Text Fragments Polyfill	Apache 2.0
The Chromium Project	BSD 3-clause "New" or "Revised" License
The USB ID Repository	BSD
Tint	Apache 2.0
UKey2	Apache 2.0
URI Template Parser	Apache 2.0
V8 JavaScript Engine	BSD
Vulkan API headers	Apache 2.0
VulkanMemoryAllocator	MIT
WDS	LGPL 2.1
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 "Expat"
Windows Template Library (WTL)	Microsoft Permissive License
Wuffs (Wrangling Untrusted File Formats Safely)	Apache 2.0
d3	BSD 3-Clause
dav1d is an AV1 decoder :)	2-Clause BSD
dom-distiller-js	BSD
dynamic annotations	BSD
fdlibm	Freely Distributable
ffmpeg	LGPL 2.1
flac	BSD
fontconfig	MIT
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
jsoncpp	MIT
libaddressinput	Apache 2.0
libavif - Library for encoding and decoding .avif files	2-Clause BSD
libbrlapi	LGPL 2.1
libevent	BSD
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
libvpx	BSD
libxml	MIT
libxslt	MIT
libyuv	BSD
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
pyjson5	Apache 2.0
pywebsocket3	New BSD
re2 - an efficient, principled regular expression library	BSD 3-Clause
simplejson	MIT
six	Apache License, Version 2.0
sqlite	Public domain
tcmalloc	BSD
test_fonts	SIL OPEN FONT LICENSE, GPL v2, Bitstream Vera Fonts Copyright
tlslite	Public domain and BSD
url_parse	BSD and MPL 1.1/GPL 2.0/LGPL 2.1
usrsctp	New BSD
v4l-utils	LGPL 2.1
valgrind	BSD
woff2	MIT
xdg-mime	Academic Free License version 2.0 or LGPL v2
xdg-user-dirs	MIT
xdg-utils	MIT
xxHash	BSD
zlib	Custom license

Qt XML Patterns

XML Schema, version 2007/08

W3C Software Notice and Document License (2015-05-13)

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 Active Qt framework	Commercial and BSD 3-clause "New" or "Revised" License.
The QtOpenGLExtensions Library	Commercial and BSD 3-clause "New" or "Revised" License.
The qtmain Library	Commercial and BSD 3-clause "New" or "Revised" License.
Trademarks	Information about trademarks owned by The Qt Company and other organizations.