SQL Server Maximum Concurrent connections and worker threads

SQL Server Maximum Concurrent connections and worker threads

Maximum number of concurrent user connections allowed by SQL Server 2008 and above is 32767

Source: http://msdn.microsoft.com/en-us/library/ms143432.aspx

Number of worker threads is

Number of CPUs	32-bit computer	64-bit computer
<= 4 processors	256	512
8 processors	288	576
16 processors	352	704
32 processors	480	960

Source: http://technet.microsoft.com/en-us/library/ms187024(v=sql.90).aspx

You can also find current thread count by using either of the queries

select max_workers_count from sys.dm_os_sys_info

select count(*) from sys.dm_os_threads