How to Easily Change Conda or Virtual Environment: Jupyter Notebook(2025)

Опубликовано: 15 Май 2026
на канале: MindVirus
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Using different Python environments within Jupyter Notebook is crucial for maintaining project isolation and managing dependencies effectively. This guide will walk you through the process for both Conda and standard virtual environments (venv) in 2025.

*1. Create and Activate Your Environment:*

Before Jupyter can see your environment, you need to create it and make it active in your terminal.

*For Conda environments:*
Open your terminal or Anaconda Prompt. To create a new environment:
`conda create --name my_project_env python=3.10` (Replace `my_project_env` with your chosen name and `3.10` with your desired Python version.)
Then, activate it:
`conda activate my_project_env`

*For Virtual Environments (venv):*
Navigate to your project's root directory in your terminal. To create a virtual environment (named `.venv` by convention):
`python -m venv .venv`
Activate it:
*Windows:* `.venv\Scripts\activate`
*macOS/Linux:* `source .venv/bin/activate`

*2. Install `ipykernel` in Your Environment:*

This is the most critical step. `ipykernel` acts as the bridge, allowing Jupyter Notebook to interact with the specific Python interpreter and packages within your newly created environment. With your environment *activated* in the terminal, run:

`pip install ipykernel`

*3. Register Your Environment as a Jupyter Kernel:*

Now, you need to tell Jupyter Notebook about this new environment so it appears as an option. While your environment is still active, execute this command:

`python -m ipykernel install --user --name=my_project_env --display-name "Python (My Project)"`

Replace `my_project_env` with the exact name of your Conda environment or `.venv` for a virtual environment.
The `--display-name` is what you will see in Jupyter's menu, so choose something descriptive like "Python (Data Analysis)" or "Python (Machine Learning)".

*4. Launch Jupyter Notebook and Select Your Kernel:*

After successfully registering the kernel, you can now launch Jupyter Notebook.

`jupyter notebook`

Jupyter will open in your web browser. To use your new environment:

Click the "New" dropdown menu, usually located on the right side of the Jupyter dashboard.
You should now see your newly registered environment listed, for example, "Python (My Project)". Select it to create a new notebook that will run using that specific environment's Python interpreter and installed packages.

*5. Change Kernel in an Existing Notebook:*

If you are already working in a Jupyter Notebook and wish to switch to a different environment:

Go to the "Kernel" menu at the top of the notebook interface.
Hover over "Change kernel."
Select your desired environment from the list that appears. The notebook will then restart with the new kernel.

*Important Notes and Troubleshooting:*

*Always Activate:* Ensure your environment is activated in your terminal before installing `ipykernel` or running the `ipykernel install` command. If `ipykernel` is installed in the wrong place (e.g., your base environment), Jupyter won't find your custom kernel.
*Verify Installation:* To see a list of all kernels Jupyter knows about, run `jupyter kernelspec list` in your terminal.
*Removing Kernels:* If you want to remove an environment from Jupyter's kernel list, use `jupyter kernelspec uninstall my_project_env` (replace `my_project_env` with the `--name` you used when installing).
*Installing Jupyter:* While `ipykernel` allows Jupyter to use your environment, you generally install `jupyter` (the notebook application itself) in your base environment or a dedicated `jupyter` environment. You do not need to install `jupyter` in every single project environment, just `ipykernel`.

By following these steps, you gain fine-grained control over your Python environments within Jupyter, leading to more organized, reproducible, and conflict-free data science and development workflows.

#JupyterNotebook
#PythonEnvironments
#CondaTutorial