Linux, FreeBSD, Juniper, Cisco / Network security articles and troubleshooting guides

How to list the largest files in a directory in Linux/FreeBSD

One of the first things to do when cleaning up a filesystem is finding old, large and no longer necessary files.

Usually on Linux and Mac laptops, directories such as “Downloads” tend to become very large in time. Old installers and archives are the first ones at eating filesystem space.

How to list all files in current directory and sort them by their size.

For files it is enough to use the “ls” command. Either with “-h” option for human readable command or without.

So this shows files sizes in human readable formats: B, KB, MB, GB and so on if we’re lucky enough (not applicable to folders are indexed representations of files so they don’t actually eat filesystem space - more on that a bit later).

What if there are few tens or even hundreds of files, it will be difficult to go through all of them and remember which is the largest.

List files in directory ordered by their size ascendantly

The “sort” command sorts the output by the 5th column (-k 5) numerically.

Listing directories and ordering by their sizes with above method is not going to work because directories do not hold data, they hold files, so they are actual index representations of filesystem blocks.
Example of a Linux system with a 4k block size:

So the actual bytes used to represent a directory are 4096, even though the contents of the directory are much larger.

List files and directories ordering by size.

The above method works for listing both for files and directories and ordering by size.