Know the SQL database size in mb kb and GB

SELECT DB_NAME(database_id) AS DatabaseName,
Name AS Logical_Name,
Physical_Name, (size*8)/1024 SizeMB,
(size*8) / 1024 AS '(MB)',
((size*8) / 1024) / 1024 AS '(GB)'
FROM sys.master_files
WHERE DB_NAME(database_id) = 'Chromalox'