Frequently Asked Questions
Qt Commercial Licensing
How long is the free evaluation period?
- Qt Commercial Licensing
- Popular
The commercial products evaluation license term is 10 days which can be extended by Qt Sales. During the initial 10 days period Qt Sales will reach out to you to check if you need additional help or a longer evaluation period.
Evaluation enables all Qt product features but may have limited access to maintenance releases. During the evaluation period, you can use the product to the full, but you are not allowed to use it for production or actual product development purposes.
After the free evaluation period, you need to a) either purchase a license or b) uninstall and cease from using the product.
Under the Qt commercial licenses, can I add new functionality and distribute Qt Creator?
- Qt Commercial Licensing
No. Distribution of Qt Creator is prohibited without a separate agreement with The Qt Company.
Yes, you can modify and add new functionality to Qt but then updates and upgrades may be an issue for you as you need to forward port your changes upon every release. In such cases, you could perhaps consider contributing your changes to Qt?
If I started development using the open source, can I later purchase a commercial license and move my code under that license?
- Qt Commercial Licensing
- Popular
This is not permitted without written consent from The Qt Company. If you have already started the development with a Qt Community Edition, please contact The Qt Company to resolve the issue. If you are unsure of which license or version to use when you start development, we recommend you contact The Qt Company to advise you on the best choice based on your development needs.
What is a term license?
- Qt Commercial Licensing
- Popular
Term licenses are legacy license types that were sold for a short period in 2018 and 2019. Current corresponding commercial licenses are "Subscription" licenses with improved terms and conditions and access also to Qt 6.
For old legacy license types, see also https://www.qt.io/terms-conditions/legacy-disclaimers
Where can I buy Qt licenses?
- Qt Commercial Licensing
- Popular
You can buy licenses directly on the online store at https://www.qt.io/pricing. If you need Distribution Licenses or Licenses for other products, then you can buy the licenses also from a sales person in your region or a reselling partner.
Which commercial Qt version grants rights to modify libraries?
- Qt Commercial Licensing
All commercially licensed Qt versions include source code and allow modification of Qt libraries.
If you need technical support for building Qt from source code, at the minimum, Standard Support offered by The Qt Company is needed. Standard Support is included almost all Subscription licenses.
If you need technical support for Qt libraries you have modified yourself, additionally sold Premium Support is required.
What does a ‘joint hardware and software distribution’ mean in practice?
- Qt Commercial Licensing
If you are making an embedded device with Qt, you most likely are creating a Device as described in the Qt Frame Agreement Appendix for Qt Development Framework and Tools. Any Device built with or incorporating Qt is subject to a distribution license fee, please contact us for more information.
Can some developers in our team working on the same project use open-source version of Qt and some developers use Commercial version of Qt?
- Qt Commercial Licensing
No. Each developer must have their own assigned Qt license. Mixing Qt commercial licenses with Qt open-source licenses in one project/product is not permitted.
My license has expired; can I continue to get new versions or updates if I do not renew the license?
- Qt Commercial Licensing
No. You must have an active license in order to get new versions/updates and receive support from The Qt Company.
I have licenses for the whole development team; can I renew it only for some members of my team?
- Qt Commercial Licensing
All the developers that develop with Qt will need to have an active license. If the whole team develops with Qt, then they all need to have a valid license.
Do the Qt commercial licenses allow for easy publishing to the Apple App Store?
- Qt Commercial Licensing
Yes. The Qt commercial licenses allow publishing to the Apple AppStore or other stores (including those that require static linking).
Can I continue to distribute my application after my developer license has expired?
- Qt Commercial Licensing
If you purchased your licenses under the Qt License Agreement 4.4 (released in Feb 2022) or later, you can continue to distribute your applications after your subscription has expired. Distribution of devices is subject to having acquired the corresponding Distribution Licenses. However, you are not allowed to make any changes to the software including bug fixes or security updates using Qt’s tools.
With older Qt License Agreements, there are more limitations on distributing the applications or using already purchased Distribution Licenses beyond the expiration of your license.
If you are unsure, you can check your License Agreement version from your Qt Account customer portal or contact Qt Sales.
Do I need to have a distribution license to distribute my application with a hardware device?
- Qt Commercial Licensing
To provide or distribute a Qt-based application on devices under Qt commercial license, distribution licenses are also required. This means if your device incorporates or integrates parts of the Qt software libraries or if the main functionality of the device depends on Qt’s products regardless of whether Qt’s products are distributed or not, then you need a distribution license.
We have started to develop a product with an open source license - How can we upgrade to a commercial Qt license?
- Qt Commercial Licensing
You can convert from developing under open source to commercial terms and conditions by contacting the Qt Company. The commercial license does not by default allow using of code created under open source license, thus you will need to contact the Qt Company to help you with the transition.
Do the commercial Qt license agreements grant the right to do static linking of Qt libraries with applications?
- Qt Commercial Licensing
Yes, unlike some open-source setups, static linking is allowed with a commercial Qt license.
I intend to access Qt's APIs through a wrapper, do I still need a license?
- Qt Commercial Licensing
Yes. Wrappers do not block the licenses of the libraries they wrap. Licenses are passed on through the wrapper, hence developers using the wrapper must comply to the wrapped libraries’ licenses.
Can I lock devices to prevent users from tampering with them when I have a commercial license?
- Qt Commercial Licensing
Yes. Locking of devices, also known as Tivoization, is allowed under the commercial license.
When do I need a Qt for Application Development and when a Qt for Device Creation license?
- Qt Commercial Licensing
- If you create a device, you need Qt for Device Creation License. When you build a hardware that incorporates, integrates, or links to parts of Qt’s software libraries, it is a device. Also, when the main intended use case of a hardware product depends on Qt’s products and there are no other means for using the hardware for its main intended use case, the hardware is considered a device.
- The Qt for Application Development license is sufficient to create applications that run on desktop PCs, mobile phones, or tablets. These kinds of computers are typically used also for reading email, browsing the Internet and so on. A Qt-based application is only one of many applications on these computers. The main use case of these computers is not dedicated to the use of your Qt-based application.
Contact us to learn more.
I have purchased a Qt for Application Development or a Qt for Device Creation subscription before 2022 - What happens at the end of my subscription?
- Qt Commercial Licensing
Your subscription will be automatically converted to the corresponding license which contains all the same features during the autorenewal at the end of the term. For licensees of the Qt for Application Development license, this will be Qt for Application Development Enterprise license. If you have a Qt for Device Creation license, then the license will be converted to an Qt for Device Creation Professional license unless you have acquired components previously licensed for the automotive industry. In that case, your license will be converted to the Qt for Device Creation Enterprise license.
I have acquired an Qt for MCUs subscription before 2022 - What will happen to my license at the end of the subscription?
- Qt Commercial Licensing
Your subscription will be automatically converted to the corresponding license which contains all the same features during the autorenewal at the end of the term. If you have the Qt for MCUs Essential package, then this will be renewed to the Qt for Device Creation Professional license. If you have the Qt for MCUs Ultimate license, then the license will be converted to an Qt for Device Creation Enterprise license.
How can I upgrade from one Qt product edition to another one?
- Qt Commercial Licensing
Please contact Qt sales for discussing the best possible upgrade choice.
Can I install Qt on one computer for coding and other Qt components on another computer as a build server?
- Qt Commercial Licensing
Yes. You can install the Qt framework and our development tools to up to five computers. Our licenses are per named individual, so all members of your team using Qt need to have a valid license. For example, Qt software running on build server established using your license may not be accessed by a user without license. Misuse may lead to payment entitlement of all applicable license fees retrospectively.
Can I use one license for multiple projects (applications or devices)?
- Qt Commercial Licensing
Yes, you can use your commercial license to design, develop or test multiple products.
A Qt for Application Development license can be used for creating Applications for generic desktop and mobile targets. Likewise, a Qt for Device Creation license can be used for all Qt for Application Development use cases as well as for creating Devices.
Only the Qt for Device Creation Distribution Licenses and Qt Extended Support are dedicated for a specific product.
When do I need a license to use Qt’s framework, tools, or libraries?
- Qt Commercial Licensing
You have two options for your product team; a) Either you comply to the Qt Community Edition open source licensing terms and conditions, or b) you purchase a commercial developer license for every developer in the team. You cannot do both.
The commercial Qt license gives you the full rights to create and distribute your software on your own terms without the open source license limitations or obligations. You will also get access to features, releases, and support that are not available for open source users.
Can a commercial license be assigned to another person?
- Qt Commercial Licensing
Yes, a license can be reassigned to another developer e.g., if there is a permanent change of job or role*. A License Manager can do this in the Qt’s customer portal.
Qt Support can nominate the License Manager from any of the license holders within the company.
*) Qt License Agreement 4.3 and older allow a license reassignment once in 6 months, Qt License Agreement 4.4 and later allow reassignment any time as long as there is a permanent change of job or role in the team.
Does Qt commercial licensing allow for source code distribution of Qt libraries or tools?
- Qt Commercial Licensing
No, it does not. Qt libraries marked as Redistributables (check Exhibit 1) may be distributed in binary form only with the application.
Do I have to purchase a commercial license for every user in our team?
- Qt Commercial Licensing
If you have chosen the commercial licensing, each Qt user must have their own assigned Qt commercial license. UI Designers, Technical Artists, Software Developers, Test Automation or Quality Assurance Engineers might have different kind of Qt licenses, but every single person needs a valid commercial license.
Also, software developers in one software project must have one type of commercial developer licenses. For example, developers working on same project cannot use both Qt for Application Development Professional and Qt for Application Development Enterprise licenses, they need to choose one license type for all team members.
It is not permitted to mix Qt commercial licensees with open source licenses. The Qt Company has the right to audit the use of commercial Qt products.
Can I distribute Qt binaries in conjunction with my desktop or mobile application?
- Qt Commercial Licensing
Yes. Distribution of Qt libraries marked as Redistributables (Exhibit 1) in binary form in conjunction with the developed application is allowed.
Can I mix different commercial license types in one project or product?
- Qt Commercial Licensing
Designer licenses can be mixed freely with developer licenses. In other words, any designer license, Qt Design Studio Professional or Enterprise, can be used with any developer license such as Qt for Application Development Professional/Enterprise or Qt for Device Creation Professional/Enterprise.
All members of the same product / project team need to have same Qt developer license type; Qt for Application Development Professional/Enterprise or Qt for Device Creation Professional/Enterprise. For example, one part of the team cannot be using a license for Qt for Device Creation Professional and another part Qt for Device Creation Enterprise as it would create difficulties to manage which user can use which feature.
Can I continue to distribute my application with my device after my license has expired?
- Qt Commercial Licensing
If you have Qt License Agreement version 4.4 (released in Feb 2022) or later: Yes, as long as you have unused Distribution Licenses, you may continue distributing your device. You can purchase more Distribution Licenses any time regardless if you have a valid developer license.
If you have Qt License Agreement version 4.3 or earlier: You have 6 months to utilize your remaining un-used Distribution Licenses after the end of your developer license term. Without a valid developer license, you cannot purchase more Distribution Licenses.
In both cases, you are not allowed to access Qt updates or use Qt tools or libraries to further develop or maintain the applications for the device. We recommend that for maintenance and security reasons you maintain at least one Qt developer license.
What is a subscription license?
- Qt Commercial Licensing
- Subscription
Customers can purchase subscription licenses for various time periods, and are entitled to use the software during the agreed upon time period. The subscription payment includes software licenses, access to support services, and new minor and maintenance versions of the software as they are released. When the subscription expires, the customer does not have rights to use commercial Qt.