How to Switch Between Python 2 and Python 3 Virtual Environments on Windows

The article explains how to create a Python virtual environment with a specific interpreter version on Windows using the virtualenv tool.

Before starting, ensure both Python 2 and Python 3 are installed on the system.

Step 1: Open a command prompt and run virtualenv -p C:\Python27\python.exe demo to create a virtual environment named demo that uses Python 2.

Step 2: After execution, the demo virtual environment is created, as shown in the screenshot.

Step 3: The environment folder appears in the current directory.

Step 4: Inside the Scripts folder you can see that the Python executable is the Python 2 version.

Step 5: Activate the environment by running activate.bat.

After activation, the command prompt shows (demo) at the beginning, indicating the virtual environment is active.

Step 6: Inside the activated environment, run python to verify that the interpreter version is Python 2.

Step 7: To exit, press Ctrl+Z or type exit() to leave Python, then run deactivate.bat.

After deactivation, the (demo) prefix disappears, confirming the environment is no longer active.

Step 8: Creating a new virtual environment without the -p option defaults to Python 3, allowing you to switch freely between Python versions as needed.