How to View All the Installed Packages on Ubuntu

1. View All the Installed Packages Using the apt Command
2. View All the Installed Packages Using dpkg-query
3. Count Number of Installed Packages in the Ubuntu System:

Sometimes, we need to use a particular package, but we are not sure whether the package exists in our system or not. Hence we need to check if the package is already installed. We can list all the installed packages on the Ubuntu system using the apt and dpkg commands.

View All the Installed Packages Using the apt Command

apt is a popular package management command-line interface introduced in Ubuntu 14.04. It can list all the installed packages in Ubuntu.

List All the Installed Packages

sudo apt list --installed

Output:

Listing... Done
accountsservice/bionic,now 0.6.45-1ubuntu1 amd64 [installed,automatic]
acl/bionic,now 2.2.52-3build1 amd64 [installed,automatic]
acpi-support/bionic,now 0.142 amd64 [installed,automatic]
acpid/bionic,now 1:2.0.28-1ubuntu1 amd64 [installed,automatic]
adduser/bionic,bionic,now 3.116ubuntu1 all [installed,automatic]
adium-theme-ubuntu/bionic,bionic,now 0.3.4-0ubuntu4 all [installed,automatic]
adwaita-icon-theme/bionic,bionic,now 3.28.0-1ubuntu1 all [installed,automatic]
cntd.......

It generates a long list of all the installed packages on our Ubuntu System, including the additional information about the version and architecture of packages.

List less Installed Packages

The command sudo apt list --installed generates a long list of all the installed packages. If we wish to pipe the output to less to make it easier to read, we can use the following command:

sudo apt list --installed | less

Check if a Particular Package Is Installed

We can check whether a particular package is installed or not by adding the grep command.

sudo apt list --installed | grep zoom

Output:

zoom/now 5.0.413237.0524 amd64 [installed,local]

It shows the zoom package installed on our Ubuntu system and the installed version of the zoom package 5.0.413237.0524.

View All the Installed Packages Using dpkg-query

apt package was introduced only after Ubuntu 14.04. If we want to list the installed packages in older Ubuntu versions, we can use dpkg-query to list all the packages.

sudo dpkg-query -l

This command lists all the installed packages in our Ubuntu system and their version, architecture, and description.

List less Installed Packages

The command sudo dpkg-query -l outputs a long list of all the installed packages. If we wish to pipe the output to less to make it easier to read, we can use the following command:

sudo dpkg-query -l| less

Check if a Particular Package Is Installed

We can check whether a particular package is installed or not using the grep command.

sudo dpkg-query -l | grep zoom

Output:

ii  zoom  5.0.413237.0524 amd64 Zoom, #1 Video Conferencing and Web Conferencing Service 

It shows the zoom package installed on our Ubuntu system and the installed version of the zoom package 5.0.413237.0524 and a short description of the package.

Count Number of Installed Packages in the Ubuntu System:

sudo dpkg-query -f '${binary:Package}\n' -W | wc -l

Output:

2008

It shows we have 2008 packages installed in our system now.