Sometimes you may not want to flip over to the Azure portal to grab the database size, such as the used space below.

So here is a handy script to run under the context of the database of interest.

SELECT
       SUM(CAST (FILEPROPERTY (name, 'SpaceUsed') AS BIGINT) * 8192.) / 1024 / 1024 / 1024  as [Database Size In GBs]
FROM sys.database_files
WHERE type_desc = 'ROWS';