[virtualenv] How can I make a list of installed packages in a certain virtualenv?

You can cd to YOUR_ENV/lib/pythonxx/site-packages/ and have a look, but is there any convenient ways?

pip freeze list all the packages installed including the system environment's.

In Python3

pip list

Empty venv is

Package    Version
---------- ------- 
pip        19.2.3 
setuptools 41.2.0

To start a new environment

python3 -m venv your_foldername_here

Activate

cd your_foldername_here
source bin/activate

Deactivate

deactivate

You can also stand in the folder and give the virtual environment a name/folder (python3 -m venv name_of_venv).

Venv is a subset of virtualenv that is shipped with Python after 3.3.

.venv/bin/pip freeze worked for me in bash.

If you're still a bit confused about virtualenv you might not pick up how to combine the great tips from the answers by Ioannis and Sascha. I.e. this is the basic command you need:

/YOUR_ENV/bin/pip freeze --local

That can be easily used elsewhere. E.g. here is a convenient and complete answer, suited for getting all the local packages installed in all the environments you set up via virtualenvwrapper:

cd ${WORKON_HOME:-~/.virtualenvs}
for dir in *; do [ -d $dir ] && $dir/bin/pip freeze --local >  /tmp/$dir.fl; done
more /tmp/*.fl

list out the installed packages in the virtualenv

step 1:

workon envname

step 2:

pip freeze

it will display the all installed packages and installed packages and versions

If you are using pip 19.0.3 and python 3.7.4. Then go for pip list command in your virtualenv. It will show all the installed packages with respective versions.

why don't you try pip list

Remember I'm using pip version 19.1 on python version 3.7.3

In my case the flask version was only visible under so I had to go to C:\Users\\AppData\Local\flask\venv\Scripts>pip freeze --local

You can list only packages in the virtualenv by pip freeze --local or pip list --local. This option works irrespective of whether you have global site packages visible in the virtualenv.

Note that restricting the virtualenv to not use global site packages isn't the answer to the problem, because the question is on how to separate the two lists, not how to constrain our workflow to fit limitations of tools.

Credits to @gvalkov's comment here. Cf. also this issue.