Jupyter Notebook opens from your command line or terminal, not from a folder or application menu

Jupyter Notebook is a browser-based tool for writing and running Python code in blocks. It does not have a clickable desktop icon or start menu entry. Instead, you launch it by typing a command into your terminal (Mac and Linux) or Command Prompt (Windows), which starts a local server and opens the notebook in your web browser.

Before you can open Jupyter Notebook, you need to have Python and Jupyter installed on your computer. Most people install both at once using a package called Anaconda, which bundles Python, Jupyter, and dozens of other data science tools together. If you have not done this yet, you will need to do that first — the installation takes about 10 minutes.

Key Takeaways

  • Jupyter Notebook runs from your terminal or Command Prompt by typing jupyter notebook, not from a clickable application.
  • You must have Python and Jupyter installed first; Anaconda is the easiest way to get both at once.
  • Jupyter opens in your web browser and creates a local server on your computer — you are not connecting to the internet.
  • The notebook saves as a .ipynb file, which you can open again by navigating to its folder and typing the same command.

Install Anaconda if you do not have Python yet

Go to anaconda.com and click the Download button. Choose the installer for your operating system (Windows, Mac, or Linux). Download the version labeled "Anaconda Individual Edition" — it is free and includes everything you need.

Run the installer and follow the prompts. On Windows, you can accept all the default settings. On Mac, the installer will guide you through the setup. The download is large (around 500 MB) and installation takes a few minutes. When it finishes, close the installer.

You do not need to open anything else after installation. Anaconda installs Python and Jupyter in the background and makes them available from your terminal or Command Prompt.

Open your terminal or Command Prompt

On Windows: Press the Windows key, type cmd, and press Enter. A black window labeled "Command Prompt" will open.

On Mac: Press Command + Space, type terminal, and press Enter. A white or black window will open.

On Linux: Right-click your desktop and select "Open Terminal", or use your application menu to find Terminal.

You now have a blank command line where you can type commands. This is where you will launch Jupyter Notebook.

Navigate to the folder where you want to save your notebook

Jupyter Notebook opens in whatever folder you are currently in. If you type the launch command from your home directory, your notebook will save there. If you want to organize your notebooks into a specific folder, navigate there first.

To move to a folder, type cd followed by the folder path. For example, on Windows you might type cd C:\Users\YourName\Documents\Python. On Mac or Linux, you might type cd ~/Documents/Python. Press Enter after typing the path.

If the folder does not exist yet, create it first using your file manager, then navigate to it. You can also type mkdir FolderName to create a new folder from the command line, then cd FolderName to enter it.

Type the command to start Jupyter Notebook

In your terminal or Command Prompt, type exactly this:

jupyter notebook

Press Enter. Jupyter will start a local server and automatically open your web browser to a page that looks like a file manager. This page shows the contents of the folder you navigated to. The URL in your browser will be something like http://localhost:8888 — the "localhost" part means the server is running on your own computer, not on the internet.

Leave your terminal or Command Prompt window open while you work. Closing it will shut down Jupyter.

Create a new notebook or open an existing one

To create a new notebook, click the New button in the top right corner of the browser window. A dropdown menu will appear. Click Python 3 (or whichever Python version you see listed). A new notebook will open in a fresh tab.

To open a notebook you have already created, navigate to its folder using the file browser that appeared when you started Jupyter, then click the notebook file. Notebook files end in .ipynb. The notebook will open in a new tab.

You can now type Python code into the cells and run it by pressing Shift + Enter. Each cell runs independently, and you can see the output directly below the code.

Close Jupyter Notebook when you are done

To stop Jupyter, go back to your terminal or Command Prompt window and press Ctrl + C (on Windows, Mac, or Linux). You will see a prompt asking if you want to shut down the notebook server. Type y and press Enter.

Your notebook file is automatically saved as you work, so you do not need to manually save before closing. The next time you want to use Jupyter, open your terminal, navigate to the same folder, and type jupyter notebook again.

Troubleshooting common problems

Command not found: If you type jupyter notebook and see an error like "command not found" or "'jupyter' is not recognized", Jupyter is not installed or not in your system path. Reinstall Anaconda and make sure to check the box that says "Add Anaconda to my PATH" during installation (Windows). On Mac, you may need to close and reopen your terminal after installing Anaconda.

Port already in use: If you see an error about port 8888 being in use, another Jupyter server is already running. Either close the other server (find its terminal window and press Ctrl + C), or start Jupyter on a different port by typing jupyter notebook --port 8889.

Browser does not open: If Jupyter starts but your browser does not open automatically, look at your terminal window. You will see a URL like http://localhost:8888/?token=abc123def456. Copy this entire URL and paste it into your browser address bar manually.

Frequently Asked Questions

Do I need an internet connection to use Jupyter Notebook?

No. Jupyter runs a server on your own computer, so you can use it completely offline. Your browser connects to localhost, not to any external website. You only need the internet if you want to download packages or data from online sources within your code.

Can I open Jupyter Notebook from a different folder each time?

Yes. Every time you open your terminal, navigate to whichever folder you want to work in, then type jupyter notebook. Jupyter will open that folder's contents in the browser. Your notebooks save in whatever folder you launched Jupyter from.

What if I close my browser tab but Jupyter is still running?

Your notebook is still open on the server. Go back to the terminal window and look at the URL shown when Jupyter started. Copy that URL into your browser to reconnect to the same notebook. Your work is not lost.

Can I run Jupyter Notebook without Anaconda?

Yes, but it is more work. You can install Python separately from python.org, then install Jupyter using pip (Python's package manager) by typing pip install jupyter in your terminal. Anaconda does this all at once, which is why it is recommended for beginners.

How do I share a notebook with someone else?

Send them the .ipynb file. They can open it by placing it in a folder on their computer, navigating to that folder in their terminal, typing jupyter notebook, and clicking the file name in the browser. They will need Python and Jupyter installed first.