Linux Survival Basics

Find the Largest Installed Packages

A Debian or Ubuntu system is low on disk and you need to see which installed packages occupy the most space.

Command

dpkg-query -W -f='${Installed-Size}\t${Package}\n' | sort -nr | head -20

What changed

Nothing changes. dpkg-query prints installed package sizes from metadata and sorts the largest first.

Danger

safe

When to use it

Use before cleanup conversations, image slimming, or deciding which package families deserve review.

When not to use it

Do not remove large packages just because they are large; kernels, runtimes, and databases may be required.

Undo or recovery

No undo needed because the command is read-only.

Expected output

A size-sorted list of installed packages by KiB.

demo script

Disposable terminal steps

dpkg-query -W -f='${Installed-Size}\t${Package}\n' | sort -nr | head -20
dpkg-query -W -f='${Installed-Size}\t${Package}\n' | sort -nr | head -5

Terminal transcript Demo JSON

simulated output

What it looks like

disposable vessel

::fixture-ready::
$ dpkg-query -W -f='${Installed-Size}\t${Package}\n' | sort -nr | head -20
132904	linux-image-6.8.0-60-generic
52288	python3
18320	nginx
8420	openssl
7488	curl
7240	libc6
6800	bash
980	base-files
256	zlib1g
250	zlib1g:i386
::exit-code::0
$ dpkg-query -W -f='${Installed-Size}\t${Package}\n' | sort -nr | head -5
132904	linux-image-6.8.0-60-generic
52288	python3
18320	nginx
8420	openssl
7488	curl
::exit-code::0

YouTube Short

Find big packages.

Before removing random packages, sort installed package sizes. Cleanup becomes evidence instead of guesswork.

experiments

A/B tests to run

Metric: save_rate

A: Disk cleanup with evidence.

B: Which packages are largest?