SQL Server Free space available in Database

This statement  will let you know what percent free space available in your selected database, this is a very useful script for those who are managing the data file size manually based on past data growth report.

SELECT AU.reserved AS Reserved_space,AU.unused as UnusedSpace,     (AU.unallocated+AU.unused)*100/(AU.reserved+AU.unallocated) AS free_space_pct FROM      (         SELECT AU.reserved,AU.reserved-AU.used AS unused,             CASE WHEN SF.db_size >= AU.reserved THEN (SF.db_size-AU.reserved) ELSE 0 END AS unallocated          FROM                   (                     SELECT                          SUM(CAST(CASE WHEN SF.status & 64 = 0 THEN SF.size ELSE 0 END AS DECIMAL(38, 2))) AS db_size                     FROM dbo.sysfiles AS SF                 ) AS SF                  CROSS JOIN                         (SELECT SUM(CAST(A.total_pages AS DECIMAL(38, 2))) AS reserved,                                 SUM(CAST(A.used_pages AS DECIMAL(38, 2))) AS used                             FROM sys.partitions AS P INNER JOIN sys.allocation_units AS A on A.container_id = P.partition_id                         ) AS AU     ) AS AU;