There are multiple ways to get the size of table in SQL Server. Lets take a look on them one by one.
Using sp_spaceused system stored procedure
Get table size using sp_spaceused system stored procedure which returns the number of rows, disk space reserved, and disk space used by a table.
Lets see the size of table ProductDetails.
Get the size of all tables in SQL Server
To get the size of all tables in SQL Server you can use stored procedure sp_MSforeachtable, it allows us to run same T- SQL query against each and every table in a single database.
Lets execute the below T-SQL, and you will see it returns the size of all tables in a database Dev_Db.
sp_msforeachtable 'EXEC sp_spaceused [?]'
Using Microsoft SQL Server Object Explorer
You can see the table size using object explorer, Go to Object explorer then right click on table as shown below.
After that, a table properties window opens. Now just click on Storage tab and on the right side under General section you will see the table size information as shown below.