ZK Licensing

ZK is offered in 3 editions, CE, PE and EE, with different features and licensing models to meet different needs. Below is a summarized table:

ZK License
Product License
ZK CE LGPL (free for open source and proprietary use)
ZK PE ZOL or Commercial License | (Free Trial available here)
ZK EE ZOL or Commercial License | (Free Trial available here)


ZK CE, licensed under LGPL offers the community the ability to use ZK CE wherever they please, including open source and commercial applications.

With this freedom we want ZK CE to be the centerpiece of our community. Therefore, we work closely with community members to achieve the common goal of creating a better platform in which all parties can leverage.

ZK PE and EE

ZK Commercial License

ZK PE and EE are available under a commercial license providing the scalability, performance, testing and support that enterprise application deployments require. Both editions have been deemed certified to deliver enterprise-level capabilities to meet the needs of even the most demanding organizations. Commercial License is the suitable option if you wish not to open source your application. For more information on pricing, please visit the pricing page.

ZK Open Source License (ZOL)

As we have strong belief in the community, we have therefore also made PE and EE's certified performance freely available to projects which are open source, under ZK Open Source License. ZOL is a free ZK license for open source projects, offered under the fair exchange basis. If your project is open source, please contact us to claim your free ZOL for PE or EE.

Recipients of a ZOL-licensed project
Each time a ZOL-licensed project is distributed, the Recipient automatically receives a License from Potix, to run and propagate his/her Developer Product subject to the ZOL License. The license does not allow Recipient to make any changes with ZK. If the Recipient will need to further develop, extend or maintain with ZK, the Recipient should contact us to claim for his/her own ZOL or commercial license for his/her extended Developer Product.

If you would like to know why you should use ZK EE please click here

ZK Tools, Extensions and Components

ZK Tools, Extensions and Components also offered under different licensing models for different purposes. Most of the add-ons are available under open source licenses, free for using in compatible projects while commercial license is the suitable option if you wish not to open source your application or if your project is not compatible to the corresponding open source license we offer. For more information on pricing, please visit the pricing page.

ZK Add-on License
ZK Tools License
ZK Studio Free to use, non-open source
ZATS Mimic GPL or Commercial
ZK Extensions License
ZK Spring GPL or Commercial
ZK JSP Tags GPL or Commercial
ZK Components License
ZK Calendar GPL or Commercial
ZK Charts Commercial
ZK CKEditor LGPL or MPL1
ZK GMaps GPL or Commercial
ZK Pivottable Commercial
Keikai Spreadsheet OSE GPL2
Keikai Spreadsheet EE Commercial2
ZK Themes License
ZK Atlantic Theme GPL or Commercial
ZK Bootstrap Add-on GPL or Commercial
ZK Theme Pack (23 themes) Commercial

1. ZK CKEditor is LGPL/MPL licensed. If you have any question on CKEditor's license please consult with corresponding 3rd party vendor directly.
2. ZK Spreadsheet is now Keikai Spreadsheet.

Feel free to contact us if you have any questions in choosing the appropriate license.