Reference : http://technet.microsoft.com/en-us/library/cc262787.aspx#Overview Web application limits The following table lists the recommended guidelines for Web applications. Limit Maximum value Limit type Notes Content database 300 per Web application Supported With 300 content databases per Web application, end user operations such as opening the site or site collections are not affected. But administrative operations such as creating a new site collection will experience decrease in performance. We recommend that you use Windows PowerShell to manage the Web application when a large number of content databases are present, because the management interface becomes slow and difficult to navigate. Zone 5 per Web application Boundary The number of zones defined for a farm is hard-coded to 5. Zones include Default, Intranet, Extranet, Internet, and custom. Managed path 20 per Web application Supported ...