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 that incorporate code licensed under third-party open-source licenses:

Qt 3D

Open Asset Import Library

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)	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	BSD 3-clause "New" or "Revised" License
FreeBSD strtoll and strtoull	BSD 3-clause "New" or "Revised" License
MD4	Public Domain
MD5	Public Domain
PCRE2	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	Creative Commons Zero v1.0 Universal
Secure Hash Algorithm SHA-3 - brg_endian	BSD 3-clause "New" or "Revised" 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	Mozilla Public License 2.0
Unicode Character Database (UCD)	Unicode License Agreement - Data Files and Software (2016)
Unicode Common Locale Data Repository (CLDR)	Unicode License Agreement - Data Files and Software (2016)
forkfd	MIT License

Qt D-Bus

libdus-1 headers

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

Qt GUI

ANGLE Library	BSD 3-clause "New" or "Revised" License
ANGLE: Array Bounds Clamper for WebKit	BSD 2-clause "Simplified" License
ANGLE: Murmurhash	Public Domain
ANGLE: Systeminfo	BSD 2-clause "Simplified" License
ANGLE: trace_event	BSD 3-clause "New" or "Revised" License
Anti-aliasing rasterizer from FreeType 2	Freetype Project License or GNU General Public License v2.0 only
Cocoa Platform Plugin	BSD 3-clause "New" or "Revised" License
Freetype 2	Freetype Project License or GNU General Public License v2.0 only
Freetype 2 - Bitmap Distribution Format (BDF) support	MIT License
Freetype 2 - Portable Compiled Format (PCF) support	MIT License
Freetype 2 - zlib	Zlib License
HarfBuzz	MIT License
HarfBuzz-NG	MIT License
IAccessible2 IDL Specification	BSD 3-clause "New" or "Revised" License
LibJPEG-turbo	Independent JPEG Group License
LibPNG	Libpng License
Native Style for Android	Apache License 2.0
OpenGL ES 2 Headers	MIT License
OpenGL Headers	MIT License
Pixman	MIT License
Smooth Scaling Algorithm	BSD 2-clause "Simplified" License and Imlib2 License
Vulkan API Registry	MIT License
Wintab API	Public Domain
XCB	MIT License
sRGB color profile icc file	International Color Consortium License
xkbcommon	MIT Licenses (with no-advertisement clause)

Qt Image Formats

JasPer	JasPer License
MNG reference library	Zlib License
TIFF Software Distribution (libtiff)	Libtiff License
WebP (libwebp)	BSD 3-clause "New" or "Revised" License

Qt Location

Boost	Boost Software License 1.0
CSS Color Parser	MIT License
Clip2Tri Polygon Triangulation Library	MIT License
Clipper Polygon Clipping Library	Boost Software License 1.0
Earcut	ISC License
Earcut Polygon Triangulation Library	ISC License
Mapbox GL Native	BSD 2-clause "Simplified" License
Poly2Tri Polygon Triangulation Library	BSD 3-clause "New" or "Revised" License
RapidJSON	MIT License
Vector Tile Library	ISC License
Wagyu Geometry Processing Library	MIT License
cURL Parse Date	MIT License
geojson-cpp	ISC License
geojson-vt-cpp	ISC License
geometry.hpp	ISC License
kdbush.hpp	ISC License
libc++	MIT and UIUC (BSD-like)
polylabel	ISC License
protozero	BSD 2-clause "Simplified" License
shelf-pack-cpp	ISC License
supercluster.hpp	ISC License
tao_tuple	MIT License
unique_resource	Boost Software License 1.0
variant	BSD 3-clause "New" or "Revised" License

Qt Purchasing

Base64 Decoder	Apache License 2.0
In-app billing service	Apache License 2.0
Public Key Verification	Apache License 2.0

Qt QML

JavaScriptCore Macro Assembler

BSD 2-clause "Simplified" License

Qt Quick Controls 2

Shadow values from Angular Material

MIT License

Qt SQL

SQLite

Public Domain

Qt SVG

XSVG	MIT "Old Style" License

Qt Script

JavaScriptCore

GNU Library General Public License v2 or later

Qt Test

Cycle	MIT License
Linux Performance Events	GNU General Public License v2.0 only with Linux Syscall Note
Valgrind	BSD 4-clause "Original" or "Old" License

Qt Virtual Keyboard

Lipi Toolkit	MIT License
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 XML Patterns

XML Schema

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
Open Source Licensing of Qt	Information about open source licensing of Qt.
The Active Qt framework	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.