According to Microsoft's documentation, the sp_spaceused stored procedure in SQL Server returns results in different units depending on the parameters provided.
For instance, when retrieving the size of the database, the result is in MB:
Size of the current database in megabytes.
sp_spaceused -- Calling without a parameter will return database_size in MB
However, for results related to tables, no specific unit is mentioned in the documentation:
Total amount of space used by data.
When passing a table name as a parameter, the results seem to be in KB, but it's not explicitly documented.
sp_spaceused 'MyTable' -- Results appear to be in KB
Is there any confirmation that the table sizes are always reported in KB, or does it depend on certain conditions?
Looking at the actual code (SQL Server 2019) in sp_SpaceUsed it is always reported in KB
BEGIN
SELECT
OBJECT_NAME (@id) AS name,
CONVERT (char(20), SUM(rows)) AS rows,
LTRIM (STR (SUM (CAST (SUBSTRING(reserved, 1, CHARINDEX(' ', reserved)) AS bigint)),15,0) + ' KB' ) AS reserved,
LTRIM (STR (SUM (CAST (SUBSTRING(data, 1, CHARINDEX(' ', data)) AS bigint)),15,0) + ' KB') AS data,
LTRIM (STR (SUM (CAST (SUBSTRING(index_size, 1, CHARINDEX(' ', index_size)) AS bigint)),15,0) + ' KB') AS index_size,
LTRIM (STR (SUM (CAST (SUBSTRING(unused, 1, CHARINDEX(' ', unused)) AS bigint)),15,0) + ' KB') AS unused
FROM
@detail_tmp_table
END