---
title: System requirements for CMS
slug: cms-11/dev-docs/system-requirements-for-optimizely
docTags: 
createdAt: 2026-07-22T19:45:18.000Z
---

:::hint{type="info"}
**Note**
These system requirements apply to versions higher than 7.5 of Optimizely Content Management System (CMS). See Install updates to CMS. See requirements and deviations below for product and service-specific requirements.
:::

## Server requirements

### Operating system

Any of the following:

- Microsoft Windows Server 2022
- Microsoft Windows Server 2019
- Microsoft Windows Server 2016 (End of support January 2022; Microsoft offers extended support options until January 2027)
- Microsoft Windows Server 2012 R2 (End of support, Microsoft offers extended support options until October 2023)
- All service packs are supported.

:::hint{type="info"}
**Note**
From CMS 9, Windows Server 2008/2008 R2 and Windows 7 are no longer supported.
:::

### Web server

- CMS 11 and lower: install any of the following as part of the Windows Server installation:
  - Microsoft Internet Information Services (IIS) 10
  - Microsoft Internet Information Services (IIS) 8.5

:::hint{type="info"}
**Note**
From CMS 9, IIS 7.0 and 7.5 are no longer supported.
:::

### Database

Any of the following:

- Microsoft Azure SQL
- Microsoft SQL Server 2019
- Microsoft SQL Server 2017 (End of support October 2022, Microsoft offering extended support options until October 2027)
- Microsoft SQL Server 2016 (End of support, Microsoft offering extended support options until July 2026)
- Microsoft SQL Server 2014 (End of support, Microsoft offering extended support options until July 2024)
- Microsoft SQL Server 2012 (End of support, Microsoft offering extended support options until July 2022)
- Microsoft SQL Server 2012 Express (End of support, Microsoft offering extended support options until July 2022)
  All service packs are supported.

:::hint{type="info"}
**Note**
From update 163, Microsoft SQL Server 2008 is no longer supported.
:::

### Other requirements

- Microsoft .NET Framework 4.6.1 and higher (CMS 11 and lower)

:::hint{type="info"}
**Note**
After 2015, Microsoft .NET Framework 4.5.0 and 4.5.1 are not supported. From CMS 11, 4.6.x is required.
:::

:::hint{type="info"}
**Note**
In a production environment, an instance bound license is required for cloud-based solutions. For non-cloud environments, a permanent IP or MAC address is required.
:::

## Client requirements for EDITING

### Browser for editing

- CMS 11 supports:
  - Mozilla Firefox, latest (b)
  - Google Chrome, latest (b)
- CMS 10 supports:
  - Microsoft Internet Explorer 11 (a)
  - Mozilla Firefox 22-57
  - Google Chrome 45-62
- CMS 9 supports:
  - Microsoft Internet Explorer 11 (a)
  - Mozilla Firefox 14-22
  - Google Chrome 33-45
- CMS 8 supports:
  - Microsoft Internet Explorer 11 (a)
  - Mozilla Firefox 11-14
  - Google Chrome 12-33

(a) For Commerce Manager, see product-specific requirements.
(b) Optimizely only supports the two latest versions for these due to fast release cycles.

## Client requirements for Browsing

- Browser for viewing – The supported web browsers depend on the implementation. Most standard web browsers are generally supported.

## Development and demonstration environment operating system

Any of the following:

- Mac OS
- Microsoft Windows 11
- Microsoft Windows 10
- Microsoft Windows 8.1 (End of support, Microsoft offers extended support options until January 2023)
- Microsoft Windows Server 2022
- Microsoft Windows Server 2019
- Microsoft Windows Server 2016 (End of support January 2022; Microsoft offers extended support options until January 2027)
- Microsoft Windows Server 2012 R2 (End of support, Microsoft offers extended support options until October 2023)

:::hint{type="info"}
**Note**
From CMS 9, Windows Server 2008/2008 R2 and Windows 7 are no longer supported.
:::

## Development tool

- CMS 11 and lower, any of the following:
  - Microsoft Visual Studio 2022
  - Microsoft Visual Studio 2019

:::hint{type="info"}
* **Notes**
  The Episerver Visual Studio integration installation requires IIS Express (included with VS 2015 and higher, can also be installed using Web Platform Installer).
* Always install the latest updates for Visual Studio.
* Visual Studio 2019 version 16.8 or higher is required for developing ASP.NET Core (CMS 12) applications.
:::

## Database

Any of the following:

- Microsoft Azure SQL
- Microsoft SQL Server 2019
- Microsoft SQL Server 2017 (End of support October 2022, Microsoft offers extended support options until October 2027)
- Microsoft SQL Server 2016 (End of support, Microsoft offers extended support options until July 2026)
- Microsoft SQL Server 2014 (End of support, Microsoft offers extended support options until July 2024)
- Microsoft SQL Server 2012 (End of support, Microsoft offers extended support options until July 2022)
- Microsoft SQL Server 2012 Express (End of support, Microsoft offers extended support options until July 2022)

:::hint{type="info"}
* **Notes**
  The Episerver Visual Studio integration installation requires SQL Server Express (included with VS 2015 and 0 higher, and can also be installed using Web Platform Installer).
* From update 163, Microsoft SQL Server 2008 is no longer supported.
:::

## Other requirements

- MVC 5.2.3 (for CMS 11)

## Product-specific requirements and deviations

### Optimizely Digital Experience Platform (DXP)

- See Requirements for Optimizely DXP.

### Optimizely Commerce Connect

- For Commerce Manager (Optimizely Commerce Connect back-end, removed in Commerce Connect 14), we recommend using Firefox or Chrome.
- ASP.NET WebForms support was dropped with version 12.1 for Commerce Connect. Note: CMS 11.x will be the last generation of CMS with ASP.NET WebForms support.

### Optimizely Forms

- Optimizely Forms is only supported by MVC-based websites and HTML5-compliant browsers.