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

PCRE2 - Stack-less Just-In-Time Compiler

BSD 2-clause "Simplified" 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 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

Mozilla Public License 2.0

TinyCBOR

MIT License

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

Bitstream Vera Font

Bitstream Vera Font License

Cocoa Platform Plugin

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

DejaVu Fonts

Bitstream Vera Font 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

WebGradients

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

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)

nunicode

MIT License

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

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 Wayland Compositor

Qt WebEngine

ARCore SDK

Apache 2.0

AXE-CORE Accessibility Audit

MPL 2.0

Abseil

Apache 2.0

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

CRC32C

New BSD

Chrome Custom Tabs - Example and Usage

Apache 2.0

ChromeVox

Apache 2.0

Chromium License

BSD

Chromium OS system API

BSD

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

Darwin

Apple Public Source License 2.0

David M. Gay's floating point routines

MIT-like

Expat XML Parser

MIT

Feed

Apache 2.0

Fiat-Crypto: Synthesizing Correct-by-Construction Code for Cryptographic Primitives

MIT

FlatBuffers

Apache 2.0

Flot Javascript/JQuery library for creating graphs

MIT

FreeType

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

GVR Android SDK

Apache 2.0

GVR Keyboard

Apache 2.0

GifPlayer Animated GIF Library

Apache License 2.0

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

MIT

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

Jinja2 Python Template Engine

BSD 3-Clause

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

Material Design Icons

Apache 2.0

Metrics Protos

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

Oculus SDK for Windows

By exception only

OpenH264

2-Clause BSD

OpenMAX DL

BSD

OpenVR SDK

BSD 3-Clause

PDFium

BSD

PLY (Python Lex-Yacc)

BSD

Paul Hsieh's SuperFastHash

BSD

Perfetto

Apache2

Protocol Buffers

BSD

Quick Color Management System

MIT

Recurrent neural network for audio noise reduction

BSD 3-Clause

SMHasher

MIT, Public Domain

SPIR-V Tools

MIT

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

The Chromium Project

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

The USB ID Repository

BSD

UnRAR source for decompressing .RAR and other files.

Non-standard

V8 JavaScript Engine

BSD

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

Yara

BSD 3-Clause

bspatch

BSD 2-Clause License

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

gestures

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

iccjpeg

Custom license

icu

MIT

inspector protocol

BSD

jsoncpp

MIT

libFuzzer

University of Illinois/NCSA Open Source

libaddressinput

Apache 2.0

libevdev

MIT

libevent

BSD

libjingle XMPP and xmllite libraries

BSD

libjpeg

Custom license

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

mach_override

MIT and 2-clause BSD

mesa

MIT and LGPL v2

minigbm

BSD

modp base64 decoder

BSD

nmoinvaz/minizip

Custom license

opus

BSD

pyjson5

Apache 2.0

re2 - an efficient, principled regular expression library

BSD 3-Clause

sfntly

Apache 2.0

simplejson

MIT

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

Apache 2.0

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

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.

© 2018 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.