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

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

PCRE

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

Parts of QTemporaryFile

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 CLDR (Unicode Common Locale Data Repository)

Unicode Data Files and Software License

forkfd

MIT License

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

HarfBuzz

MIT License

HarfBuzz-NG

MIT License

IAccessible2 IDL Specification

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

LibJPEG

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

Wintab API

Public Domain

XCB

MIT License

at-spi2 (Assistive Technology Service Provider Interface)

GNU Library General Public License v2 or later

xkbcommon

MIT Licenses (with no-advertisement clause)

Qt Help

Clucene Core Library

GNU Lesser General Public License v2.1 only or Apache License, Version 2.0

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

Clip2Tri Polygon Triangulation Library

MIT License

Clipper Polygon Clipping Library

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 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

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 Wayland Compositor

Qt WebEngine

Almost Native Graphics Layer Engine

BSD

American Fuzzy Lop

Apache 2.0

Android Explicit Synchronization

Apache 2.0

Blackmagic DeckLink SDK - Mac

BSL (v 1.0)

Brotli

MIT

Chrome Custom Tabs - Example and Usage

Apache 2.0

ChromeVox

Apache 2.0

Chromium License

BSD

Chromium OS system API

BSD

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

Crashpad

Apache 2.0

Darwin

Apple Public Source License 2.0

David M. Gay's floating point routines

MIT-like

Error Prone

Apache 2.0

Expat XML Parser

MIT

FlatBuffers

Apache 2.0

Flot Javascript/JQuery library for creating graphs

MIT

FreeType

Custom license "inspired by the BSD, Artistic, and IJG (Independent

GifPlayer Animated GIF Library

Apache License 2.0

Google Cardboard

Apache 2.0

Google fork of Khronos reference front-end for GLSL and ESSL

MIT

Hardware Composer Plus

Apache 2.0

Headless Android Heap Analyzer

Apache 2.0, LGPL 2.1

IAccessible2 COM interfaces for accessibility

BSD

ISimpleDOM COM interfaces for accessibility

MPL 1.1/GPL 2.0/LGPL 2.1

Khronos header files

MIT/X11, SGI Free Software License B

LZMA SDK

Public Domain

LeakCanary

Apache 2.0

LevelDB: A Fast Persistent Key-Value Store

New BSD

NSBezierPath additions from Sean Patrick O'Brien

BSD

NVidia Control X Extension Library

MIT

Netscape Portable Runtime (NSPR)

MPL 1.1/GPL 2.0/LGPL 2.1

Network Security Services (NSS)

MPL 2

OTS (OpenType Sanitizer)

BSD

OpenH264

2-Clause BSD

OpenMAX DL

BSD

PDFium

BSD

PLY (Python Lex-Yacc)

BSD

Paul Hsieh's SuperFastHash

BSD

Protocol Buffers

BSD

Quick Color Management System

MIT

SMHasher

MIT, Public Domain

SPIR-V Tools

MIT

Shaderc

Apache 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 software renderer.

Proprietary

The USB ID Repository

BSD

The library to input, validate, and display addresses.

Apache 2.0

V8 JavaScript Engine

BSD

Vulkan API headers

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

Windows Template Library (WTL)

Microsoft Permissive License

blimp_fonts

Apache Version 2.0 and SIL Open Font License, Version 1.1

boringssl

BSDish

bspatch

BSD Protection license

class-dump

NOT_SHIPPED

d3

BSD 3-Clause

dom-distiller-js

BSD

dynamic annotations

BSD

fdlibm

Freely Distributable

ffmpeg

LGPL 2.1

fips181

BSD 3-Clause

flac

BSD

fontconfig

MIT

gRPC, an RPC library and framework

BSD-style, copyright Google

google-glog's symbolization library

BSD

google-jstemplate

Apache 2.0

harfbuzz-ng

MIT

hunspell

MPL 1.1/GPL 2.0/LGPL 2.1

iccjpeg

Custom license

icu

MIT

jsoncpp

MIT

libFuzzer

University of Illinois/NCSA Open Source

libcxx

MIT, University of Illinois/NCSA Open Source License

libcxxabi

MIT, University of Illinois/NCSA Open Source License

libevent

BSD

libjingle

BSD

libjpeg

Custom license

libjpeg-turbo

Custom license

libpng

libpng license

libsecret

LGPL 2.1

libsrtp

3-clause BSD

libudev

LGPL 2.1

libusbx

LGPL 2.1

libva

MIT

libvpx

BSD

libxml

MIT

libxslt

MIT

libyuv

BSD

linux-syscall-support

BSD

mach_override

MIT and 2-clause BSD

mesa

MIT and LGPL v2

minigbm

BSD

modp base64 decoder

BSD

mt19937ar

BSD

open-vcdiff

Apache 2.0, MIT, GPL v2 and custom licenses

opus

BSD

re2 - an efficient, principled regular expression library

BSD 3-Clause

sfntly

Apache 2.0

simplejson

MIT

sqlite

Public domain

tcmalloc

BSD

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

wayland

MIT

wayland-protocols

MIT

woff2

Apache 2.0

x86inc

ISC from text in file header. Same text is copied to LICENSE file.

xdg-mime

Academic Free License version 2.0 or LGPL v2

xdg-user-dirs

MIT

xdg-utils

MIT

yasm

2-clause or 3-clause BSD licensed, with the exception of bitvect, which is triple-licensed under the Artistic license, GPL, and LGPL

zlib

Custom 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

Contributions to the Cocoa Platform Plugin Files

License information for contributions by Apple, Inc. to specific parts of the Qt for macOS Cocoa port.

Flite Library

Licenses for Fonts Used in Qt for Embedded Linux

Information about the licenses of fonts supplied with Qt

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 qtmain Library

Commercial and BSD 3-clause "New" or "Revised" License.

Trademarks

Information about trademarks owned by The Qt Company and other organizations.

© 2017 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.