There are several ways to Shrink TempDB:
Method 1:
Restart SQL Server, it will create new empty TempdB.
Method 2:
DBCC FREEPROCCACHE
GO
USE [tempdb]
GO
DBCC SHRINKFILE (N’tempdb’ , 5000)
GO
Method 3:
Run the following Transact-SQL commands:
ALTER DATABASE tempdb MODIFY FILE (NAME = 'tempdev', SIZE = target_size_in_MB)
--Desired target size for the data file
ALTER DATABASE tempdb MODIFY FILE (NAME = 'templog', SIZE = target_size_in_MB)
--Desired target size for the log file
