To [check the size of a directory](https://www.howtouselinux.com/post/check-directory-size-in-linux) in Ubuntu, you can use the du command. This command stands for "disk usage" and it shows the amount of disk space used by the specified files or directories.

Options:

```plaintext
-h , --human-readable

-s, --summarize

-a, --all

-c, --total

--max-depth
```

To use the du command, open a terminal window and navigate to the directory whose size you want to check. Then, type du followed by the name of the directory, like this:

```plaintext
du /path/to/directory
```

This will display the size of the directory in kilobytes. **If you want to see the size of all the files and directories inside the specified directory, you can use the** `-a` **option like this:**

```plaintext
du -a /path/to/directory
```

This will display the size of each file and directory inside the specified directory, along with the total size at the end.

**You can also use the -h option to display the size in a more readable format, such as megabytes or gigabytes,** like this:

```plaintext
du -ah /path/to/directory
```

This will display the size of each file and directory in the specified directory in a human-readable format.

If you only want to get the total size of the directory, you can use -s option like this:
```
du -sh /path/to/directory
```

Overall, the du command is a useful tool for checking the size of directories in Ubuntu.