Note: WebSharper 3 is licensed under Apache 2. This page applies to WebSharper 2 only.

Open source license

Create open source apps and websites with WebSharper for free under the terms of GNU AGPL v3 or another open source license of your choice.

AGPL v3 Exceptions
Closed source license

Use WebSharper to develop end-user apps and keep their source code proprietary. You cannot develop SDKs or toolkits under this license.

Terms Buy
OEM license

Use and redistribute WebSharper in your own SDKs, software libraries or frameworks. Contact us for individual terms that would work for your project.


Licensing FAQ

I have a license to WebSharper 1.x - can I use it with WebSharper 2.5?

No, WebSharper 1.x licenses are only valid for that major version.

I have a license to WebSharper 2.4 - can I use it with WebSharper 2.5?

Yes, 2.x licenses prior to 2.5 cover 2.5 as well.

I see that licensing changed with 2.5, how does that affect me?

Existing 2.x licenses are unaffected, they continue to cover 2.5 permanently, you don't need to renew every year. However, starting with 2.5, new licenses are per year and need to be renewed yearly to continue coverage.

You mean I have to continue renewing to use WebSharper?

No. If you don't renew, you will still be able to use the latest WebSharper and any extension you obtained when your license was valid, as long as those are the same MAJOR version as those available at the beginning of your last licensing period, and you can continue to use those binaries indefinitely. However, you will not benefit from any updates and bugfixes, as those require an ongoing license.

You mean if my license expires shortly after a new major version (say, 3.0) comes out, I can't use that without renewing?

Yes, that's correct. You will need to renew if there is a new major release before your license expires to be able to use that new major version.

If we are a company, can we get away by renewing on an individual license?

No, as a company you can only renew using a corporate license.

What changed in WebSharper 2.5+ licensing?

WebSharper 2.5 introduces new licensing terms. The main difference is that instead of permanent developer and yearly support licenses, we now offer yearly licenses only, with the option of a much more cost effective single-developer option. For the regular licenses (Start-up and Enterprise) various levels of support are included. Please refer to the Support page for more details.

What are public/private/premium extensions?

WebSharper extensions bring client-side APIs to consuming WebSharper applications. Extensions are licensed together with WebSharper on the same licensing terms: thus, their royalty-free use is only allowed on open source projects.

Public extensions are available on Nuget and are themselves open source, serving as examples to those who are working on developing WebSharper extensions. You can check the sources of these extensions and contribute enhancements and fixes by submitting pull requests, the repositories are collected on the Downloads page.

Private extensions are also available on Nuget, but their source code is not available publically. To use private extensions you must have a valid license, even if you are using WebSharper in an open source project.

Premium extensions require a company license to use, otherwise they are similar to private extensions. If you are an individual license holder and would like to use any premium extensions, contact us for additional licensing.

I would like to develop an open source project, do I need to get a license?

No, for open source applications compatible with GNU AGPL v3, or those listed under the open source license exceptions, you may use WebSharper without a developer license. However, depending on the extensions you use, you may need to acquire a license - see above.

My open source project is not GNU AGPL v3, can I still use WebSharper without a developer license?

Absolutely! There are a number of other FLOSS licenses that you can use with WebSharper, as listed as open source license exceptions.

I have a developer license, how long is it valid?

If you have a WebSharper 2.x (prior to 2.5) developer license it is valid forever for any WebSharper 2.x release, including 2.5. If you have a WebSharper 2.5 or higher license, it is valid for the duration of your license purchase, and need to be renewed once it expires to continue receiving updates.

As a licensed developer, does my customer need a license to host/deploy the application I am developing?

No, a WebSharper developer license allows that you distribute your WebSharper applications to your customers without requiring further licenses on their end to host and deploy these applications. However, these applications can only be modified by those who have developer licenses.

I have a valid WebSharper 2.4 support license, what coverage does that enable in the new licensing structure?

WebSharper 2.4 support licenses are translated to Start-up coverage, from the time of the first WebSharper 2.5 public release.

What is the difference between a Freelancer and the other closed-source licenses?

All closed-source licenses (Freelancer, Start-up, Business) enable you to develop applications without having to provide their full source code to the general public.

A Freelancer license, however, does not include any support and comes with limited ability to use various WebSharper extensions.

The company licenses (Start-up and Business) provide you with a number of important benefits. These include elevated priority on public forums, telephone and email support for technical queries, hotfixes, guaranteed response times, and support for private and premium extensions (see Store for details).

Open source licensing exceptions

Terms and conditions

This Exception applies to open source applications built with WebSharper and WebSharper extensions ("The Software"), and to open source Derivative Works of the Software, that use the Software under the terms of GNU Affero General Public License, version 3 ("AGPLv3"). The Exception extends AGPLv3 by providing additional grants.

You are permitted to distribute Derivative Work that includes or is based on the Software, in combination with other software licensed under the licenses from the list below, provided that:

You obey the AGPLv3 terms for the Software and the Derivative Work, except for the separate parts of the Derivative Work ("Additions") which constitute independent work and are not dervied from the Software.

All Additions are distributed subject to one of the licenses listed below.

Your software distribution provides complete source code for the Additions.

The Derivative Work and its Additions are intended for use in end-user applications and do not constitute software intended for use by software developers, such as software libraries, components, and development kits.

If you violate any of the terms in this Exception, you lose all rights granted to you by the Exception and revert to the terms of AGPLv3.

Open source license list
Name Version
Academic Free License 2.0
Apache Software License 2.0
Apple Public Source License 2.0
Artistic license From Perl 5.8.0
BSD license July 22 1999
Common Development and Distribution License (CDDL) 1.0
Common Public License 1.0
Eclipse Public License 1.0
Educational Community License 2.0
European Union Public License (EUPL) 1.1
GNU General Public License (GPL) 2.0
GNU Library or "Lesser" General Public License (LGPL) 3.0
Jabber Open Source License 1.0
MIT License (as listed in file MIT-License.txt) -
Mozilla Public License (MPL) 1.0/1.1
Open Software License 2.0
OpenSSL license (with original SSLeay license) 2003 (1998)
University of Illinois/NCSA Open Source License -
W3C License 2011
X11 License 2001
Zlib/libpng License -

WebSharper developer license

This Agreement governs the relationship between you, a private person, or the organization on whose behalf you are acting ("You"), and IntelliFactory ("Us") with respect to using WebSharper ("The Software"). The Agreement sets the terms, rights, restrictions and obligations on your use of The Software.

License Grant

We grant You a non-assignable, non-transferable, non-exclusive, non-sublicenseable, royalty-free, revocable license (1) for Your employee, consultant or contractor ("Developer"), acting within the scope of their services provided for You or on your behalf, to install the Software on a single computer they operate personally and exclusively; (2) for You to use the Software to create and operate unlimited applications and websites on unlimited servers, domains and sub-domains, and to distribute components of the Software required to use such applications and websites, subject to distribution restrictions stated below; (3) for you to create derivative works, as detailed below.

If You purchase a Team, Workgroup or any other license package from Us, a number of Developers will be able to operate the Software under this Agreement on their personal computers as specified in (1). The number of Developers is defined when purchasing the license package.

This Agreement does not constitute a sale: We reserve ownership of all intellectual property rights related to the Software.

Permitted Uses
  1. Distribution: You can distribute the Software or parts thereof in any applications, websites or products that you develop using the Software, provided they do not violate the conditions stated below as PROHIBITED USES. You must not remove or otherwise interfere with any copyright and attribution statements incorporated in the Software. You must make sure that the Software is not used by Your customers and other third parties independently of Your applications.
  2. Modifications: You may create Modifications of the original Software. Modification is defined as any edit or addition to the files included in the Software. While You retain all rights to Modifications you have authored, We retain all intellectual property rights and copyright inherent in the original Software.
Prohibited Uses

You may not redistribute the Software or Modifications other than by including the Software within Your own applications, websites and products that offer substantially different functionality from the Software itself. Under this Agreement You are explicitly prohibited to redistribute the Software or Modifications as software libraries, toolkits or any other products targeted for use by software developers.

Additional Licenses

Portions of the Software files constitute redistribution of third-party software, and are subject to separate license terms, including:

  1. jQuery:
  2. Mono Cecil:

This Agreement terminates immediately and without notice if You fail to comply with any of its terms and conditions. In case of a termination, You agree to stop using the Software immediately.

Prior Inspection

You hereby state that you have inspected the Software thoroughly and found it satisfactory and adequate to your needs, that it does not interfere with your regular operation and that it meets the standards and scope of your computer systems and architecture.

You have found that the Software is compatible with your computing environment and that it does not infringe on any End User License Agreement of any software You may use in performing your services. You hereby waive any claims regarding the Software's incompatibility, performance, results and features, and warrant that You have inspected the Software.

Limitation of Liabilities

To the maximum extent permitted under law, the Software is provided without any warranty, under an AS-IS basis. You hereby disclaim all warranties and conditions, including, but not limited to the warranty that the Software shall be error free, without defects, fit for a particular purpose, or continuously operational. We shall never be liable for any damage, cost, expense or any other payment incurred by You as a result of Software's actions, failure, bugs and/or any other interaction between the Software and your equipment, computers, or business services. In all circumstances, our entire liability under this Agreement shall be limited to ONE (1) US dollar.

Support and Updates

Software is provided without any support, which should be purchased separately. Nothing in this Agreement shall require Us to provide You with support or fixes to any bug, failure, or other defect in the Software.

We will provide software updates at our own discretion. Under this Agreement You are entitled to minor version updates (for example, 2.4.*, 2.5.*, 2.6.*), but not major version updates (for example, 3.*, 4.*) or fixes (such as 2.4.101, 2.4.102), which are available separately for purchase.