I am a bit confused with PyQt6 licensing and Qt Licensing. I’m planning on developing a commercial app using python and pyqt6. I will not use Qt Designer at all. In my case would I need to purchase only the PyQt commercial license? or do I need to purchase a Qt license too?
I am also planning the same. Based on what I have read, I think if we don’t use the Qt Designer at all then we don’t need to purchase any commercial license.
Hi @Jay and welcome to the forum.
Licensing isn’t affected by whether you use Qt Designer. You may be confusing Qt Designer with Qt Design Studio which has a paid version. Qt Designer is free to use and doesn’t affect licensing.
The short version —
- PySide6 is LGPL licensed. This means you don’t need a commercial license (from Qt) to distribute your application without distributing the source (see caveats below).
- PyQt6 is GPL licensed. This means that you do need a commercial license (from Riverbank Software) to distribute your application without distributing the source.
If you distribute under terms which are incompatible with the LGPL you would need a commercial Qt license (for PySide6 and in addition to the Riverbank license for PyQt6). Also some parts of Qt, such as QtCharts and Qt Data Visualization are also GPL licensed, and so would require a commercial license unless you’re also using the GPL. But most projects don’t require one.
For more information see this longer article.