How to Show All Databases in MongoDB Quickly

To show all databases in MongoDB, use the show dbs command in the MongoDB shell. Alternatively, you can run db.adminCommand({ listDatabases: 1 }) to get detailed database info.

Syntax

The main ways to list databases in MongoDB are:

• show dbs: A shell command that lists all databases with their sizes.
• db.adminCommand({ listDatabases: 1 }): A command that returns detailed info about all databases in JSON format.

mongodb

show dbs

// or

db.adminCommand({ listDatabases: 1 })

Example

This example shows how to list all databases using the MongoDB shell.

mongodb

mongosh
> show dbs

// Output might look like:
// admin   0.000GB
// local   0.000GB
// mydb    0.001GB

// Using adminCommand:
> db.adminCommand({ listDatabases: 1 })
{
  "databases" : [
    { "name" : "admin", "sizeOnDisk" : 83886080, "empty" : false },
    { "name" : "local", "sizeOnDisk" : 83886080, "empty" : false },
    { "name" : "mydb", "sizeOnDisk" : 1048576, "empty" : false }
  ],
  "totalSize" : 178257920,
  "ok" : 1
}

Output

admin   0.000GB
local   0.000GB
mydb    0.001GB

{
  "databases" : [
    { "name" : "admin", "sizeOnDisk" : 83886080, "empty" : false },
    { "name" : "local", "sizeOnDisk" : 83886080, "empty" : false },
    { "name" : "mydb", "sizeOnDisk" : 1048576, "empty" : false }
  ],
  "totalSize" : 178257920,
  "ok" : 1
}

Common Pitfalls

Some common mistakes when trying to list databases:

• Running show dbs outside the MongoDB shell will not work because it is a shell-specific command.
• Databases with no collections or data may not appear in the list because MongoDB does not create empty databases.
• Using db.getMongo().getDBNames() is deprecated in newer MongoDB versions; prefer show dbs or db.adminCommand({ listDatabases: 1 }).

mongodb

/* Wrong: Using deprecated method */
> db.getMongo().getDBNames()

/* Right: Use this instead */
> show dbs

/* Or */
> db.adminCommand({ listDatabases: 1 })

Quick Reference

Command	Description
show dbs	Lists all databases with their sizes in the shell
db.adminCommand({ listDatabases: 1 })	Returns detailed JSON info about all databases
db.getMongo().getDBNames()	Deprecated method to list databases, avoid using

Key Takeaways

Use show dbs in the MongoDB shell to quickly list all databases.

For detailed info, use db.adminCommand({ listDatabases: 1 }).

Empty databases without collections won't appear in the list.

Avoid deprecated methods like db.getMongo().getDBNames().

Run these commands inside the MongoDB shell, not in a regular terminal.