PSQL: Get The Size Of A Database

If you have connect access to a PostgreSQL database, you can use the pg_database_size() function to get the size of a database in bytes.

> select pg_database_size('hr_hotels');
 pg_database_size
------------------
          8249516

Just give it the name of the database and it will tell you how much disk space that database is taking up.

Checkout the Postgres docs for more details.

Via jbranchaud/til.