Jupyter Notebook is a web-based interface for writing and running Python code. You can launch it directly from your command prompt or terminal in just a few seconds. This guide shows you exactly how to do it, plus troubleshooting tips if something doesn’t work
Open your command prompt (Windows) or terminal (Mac/Linux). Type this command and press Enter:
jupyter notebook
That’s it. Your browser will open with Jupyter Notebook running. You can now create and edit notebooks.
Prerequisites: Do You Have Jupyter Installed?
Before you can open Jupyter from the command line, you need to have it installed. Most people install it through pip, which is the Python package manager.
Check if Jupyter is already installed by typing this in your command prompt:
jupyter --version
If a version number appears, you’re ready to go. If you see “command not found” or “is not recognized,” you need to install it first.
How to Install Jupyter Notebook
Installation takes about two minutes.
Using pip (Recommended)
Pip comes with Python. Use this command:
pip install jupyter
Wait for the installation to complete. You should see “Successfully installed” at the end.
Using Anaconda
If you already have Anaconda installed on your computer, Jupyter comes pre-installed. You don’t need to do anything special.
Using conda (Anaconda Users)
If you want to install or update Jupyter through Anaconda:
conda install jupyter
Step-by-Step: Opening Jupyter Notebook from CMD
For Windows Users
- Press the Windows key and type “cmd”
- Click on “Command Prompt“
- Type:
jupyter notebook - Press Enter
- Your default browser opens with Jupyter running
The terminal will show several lines of information, including a local URL that looks like http://localhost:8888. This is normal and means everything is working.
For Mac Users
- Open Spotlight (Command + Space)
- Type “terminal”
- Press Enter to open Terminal
- Type:
jupyter notebook - Press Enter
- Your browser opens with Jupyter ready to use
For Linux Users
- Open your terminal (usually Ctrl + Alt + T)
- Type:
jupyter notebook - Press Enter
- Your browser launches Jupyter
Opening Jupyter in a Specific Folder
By default, Jupyter opens in your home directory. If your project files are somewhere else, navigate to that folder first.
Use the cd command to change directories:
cd C:\Users\YourName\Documents\MyProject
On Mac or Linux:
cd ~/Documents/MyProject
Then type:
jupyter notebook
Now Jupyter opens with your project folder as the starting location.
Useful Command Options You Should Know
Start Jupyter on a Specific Port
By default, Jupyter uses port 8888. If you want to run multiple Jupyter instances, use a different port:
jupyter notebook --port 8889
Open a Specific Notebook File
Instead of opening the file browser, you can open a notebook directly:
jupyter notebook myfile.ipynb
Launch Without Opening Your Browser
Sometimes you want Jupyter running without automatically opening a browser window:
jupyter notebook --no-browser
Then copy the URL from the terminal and paste it into your browser manually.
Run Jupyter in Read-Only Mode
This prevents accidental changes to notebooks:
jupyter notebook --read-only
Disable Token Authentication
If you’re running Jupyter only locally and want to skip the token (not recommended for security):
jupyter notebook --ip=localhost --no-browser
What Happens When You Launch Jupyter
When you type jupyter notebook and press Enter, several things happen instantly:
A local server starts running on your computer. This server runs in the background at an address like http://localhost:8888. Your command prompt shows you this information.
Your default web browser automatically opens and connects to this address. The Jupyter interface loads, showing you a file browser.
You can now create new notebooks, open existing ones, or upload files. Everything you do in the browser is processed by the server running in your command prompt.
When you close your browser tab, Jupyter keeps running. To stop it, return to your command prompt and press Ctrl + C, then press Y to confirm. The server shuts down.
Troubleshooting Common Problems
Problem: “jupyter is not recognized”
This means Jupyter is not installed or Python is not in your system PATH.
Solution 1: Install Jupyter using pip.
pip install jupyter
Solution 2: If pip is not recognized, you may need to reinstall Python and make sure to check the “Add Python to PATH” option during installation.
Solution 3: Use the full path to Jupyter:
python -m jupyter notebook
This works even if Jupyter is not in your PATH.
Problem: Browser Won’t Open Automatically
Sometimes Jupyter launches but your browser doesn’t open.
Solution: Copy the URL from your command prompt (it looks like http://localhost:8888/?token=abc123...) and paste it directly into your browser’s address bar.
Problem: “Address already in use”
This happens when another application is using port 8888.
Solution: Use a different port:
jupyter notebook --port 8889
Or close the other Jupyter instance using Ctrl + C in its command prompt.
Problem: Permission Denied Error
This occasionally happens on Mac or Linux.
Solution: Try this command:
python -m jupyter notebook
If that doesn’t work, reinstall Jupyter:
pip install --upgrade jupyter
Problem: Jupyter Runs Slowly or Freezes
Large notebooks can slow things down.
Solution 1: Close other applications using your computer’s memory.
Solution 2: Restart Jupyter by pressing Ctrl + C in your command prompt, then type jupyter notebook again.
Solution 3: If a specific notebook is causing problems, open a new one and transfer your code gradually.
Best Practices for Using Jupyter from CMD
Always Navigate to Your Project Folder First
Before launching Jupyter, use cd to go to the folder containing your project. This keeps your files organized and easy to find.
Use Virtual Environments
Python virtual environments keep your projects isolated from each other. Create one like this:
python -m venv myenv
Activate it (Windows):
myenv\Scripts\activate
Activate it (Mac/Linux):
source myenv/bin/activate
Then install Jupyter in this environment and launch it. This prevents conflicts between project dependencies.
Keep a Terminal Window Open While Working
Leave your command prompt or terminal window open while using Jupyter. This window shows you error messages and helps you understand what’s happening behind the scenes.
Save Your Notebooks Regularly
Jupyter auto-saves, but don’t rely on it completely. Use Ctrl + S to save manually, especially after important work.
Alternative Ways to Launch Jupyter
From Python
You can also start Jupyter directly from Python:
python
Then in Python:
import subprocess
subprocess.Popen(['jupyter', 'notebook'])
Exit Python with exit().
Using Jupyter Lab (Advanced Alternative)
Jupyter Lab is a newer, more advanced interface. If you have it installed, launch it with:
jupyter lab
It works the same way but offers more features and a modern interface.
Using Anaconda Navigator
If you use Anaconda, click the Navigator application, find Jupyter Notebook in the list, and click “Launch.” This does the same thing as using the command line, but with a graphical interface.
Launching Methods
| Method | Command | Best For | Difficulty |
|---|---|---|---|
| Command Prompt/Terminal | jupyter notebook | Daily use, quick launches | Very Easy |
| Anaconda Navigator | Click Launch button | Users who prefer GUIs | Easy |
| Jupyter Lab | jupyter lab | Advanced workflows | Easy |
| Python subprocess | Use Python code | Automation | Medium |
| Specific notebook | jupyter notebook file.ipynb | Opening saved work | Easy |
| No browser | jupyter notebook --no-browser | Remote servers | Medium |
Getting Help When Something Goes Wrong
Check Jupyter Documentation
The official Jupyter documentation has detailed guides for every issue.
Verify Your Python Installation
Make sure Python is working properly:
python --version
You should see a version number like “Python 3.9.7” or higher.
Search for Your Specific Error
Take the exact error message from your command prompt and search for it online. Stack Overflow and GitHub issues often have solutions to specific problems.
Summary
Opening Jupyter Notebook from your command prompt is straightforward. Type jupyter notebook and press Enter. Your browser opens with Jupyter running. Before your first launch, make sure you have Jupyter installed using pip install jupyter. Navigate to your project folder using the cd command if you want Jupyter to start in a specific location. If something doesn’t work, check that Python is installed, Jupyter is in your PATH, and that port 8888 isn’t in use. Once you’re comfortable with the basics, explore options like specifying ports, running without a browser, and using virtual environments to enhance your workflow.
Frequently Asked Questions
Why does my browser open to a blank page?
Give it a few seconds to load. If it stays blank, check your command prompt for error messages. The URL might have an invalid token. Try copying the full URL from the command prompt and pasting it in your browser.
Can I run Jupyter on a different computer and access it remotely?
Yes, you can configure Jupyter to accept remote connections, but this requires careful security setup. Check the Jupyter documentation on security and configuration for remote access instructions.
Do I need to reinstall Jupyter after updating Python?
Not necessarily, but it’s good practice to reinstall it after a major Python update. Use pip install --upgrade jupyter to ensure compatibility.
How do I stop Jupyter from running?
Press Ctrl + C in your command prompt or terminal. You’ll be asked to confirm. Press Y and Enter. The Jupyter server stops immediately.
What’s the difference between Jupyter Notebook and Jupyter Lab?
Jupyter Lab is the newer, more advanced interface with a file browser, text editor, and terminal all in one application. Jupyter Notebook is simpler and faster for basic work. Both use the same notebook files and can be launched from the command line the same way.
