How to convert sys.master_files size column into GB

Question: I need to convert the sys.master_files size column into GB. Currently when I run select name,size from sys.master_files I get back the file size as KB. I've tried doing something    - size/1024/1024 - but I'm getting incorrect results.    

How do I get the current sys.master_files size unit into the GB format?

Answer: The size column in the sys.master_files is an int data type and is represented as 8-KB pages. In the example you've given above - you're not taking into account the 8-KB pages.    You need to multiply the size value by 8. i.e size * 8

Find an example of converting the 8-KB pages within a SQL statement. I also like cast the size column for greater accuracy.

select name,(cast(size as float)*8)/1024/1024 as FILE_SIZE_GB
 from sys.master_files 

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