Run Node-RED: Build Automations Without Writing Code

// Before you start

What you need

A computer running Windows, Mac, or Linux
Node.js installed (download from nodejs.org — LTS version recommended)
npm included with Node.js install
A terminal or command prompt you can open

Step 1 of 5

Verify Node.js is installed

1 min

Before installing Node-RED, confirm Node.js is already on your machine. This command prints the version number. If you see a number like v18.x.x or v20.x.x, you are good to go. If you get an error, visit nodejs.org, download the LTS installer, run it, then come back here.

Terminal · mac

$ node --version

What you should see

v18.20.0 (or any v18 / v20 number)

This might happen

Command not found or version is below v14

Download and install the LTS release from https://nodejs.org then open a fresh terminal window and try again.

Step 2 of 5

Install Node-RED globally

3 min

This single command downloads Node-RED and makes it available as a command you can run any time. The --unsafe-perm flag is required on Linux and Mac to avoid permission errors during install. On Windows you can omit it, but it does not hurt to include it. The install may take a minute or two — you will see a lot of text scroll by; that is normal.

Terminal · mac

$ sudo npm install -g --unsafe-perm node-red

What you should see

added NNN packages ... npm warn ... (no red ERROR lines)

This might happen

Permission denied errors on Mac or Linux

Make sure you typed sudo at the start. It will ask for your system password — type it and press Enter (the cursor will not move while you type, that is normal).

Step 3 of 5

Start Node-RED

1 min

This launches the Node-RED server on your machine. It will print a few lines of startup info and then sit there running. Leave this terminal window open the entire time you use Node-RED — closing it shuts the server down.

Terminal · mac

$ node-red

What you should see

Welcome to Node-RED =================== ... Server now running at http://127.0.0.1:1880/

This might happen

Port 1880 is already in use

Another app is using that port. Stop it, or run Node-RED on a different port with: node-red -p 1881

Step 4 of 5

Open the visual editor in your browser

1 min

With the server running, open any web browser and go to the address below. You will see the Node-RED flow editor — a canvas on the left, a panel of nodes on the right, and a toolbar at the top. This is where you build everything by dragging and connecting blocks.

Terminal · mac

$ open http://localhost:1880

What you should see

The Node-RED flow editor loads in your browser with an empty canvas.

This might happen

Browser shows 'This site can't be reached'

Check that the terminal running node-red is still open and shows no errors. Try typing the address manually: http://localhost:1880

Step 5 of 5

Build and deploy your first flow

5 min

Drag an 'inject' node from the left panel onto the canvas, then drag a 'debug' node next to it. Click the grey dot on the right side of the inject node and drag a line to the grey dot on the left side of the debug node — this wires them together. Click the red 'Deploy' button in the top-right corner to save and activate your flow. Now click the button on the inject node. Switch to the 'Debug' tab in the right panel and you will see a message appear. That is your first working automation.

Terminal · mac

$ No command needed — this step is done entirely in the browser.

What you should see

A message such as '1234567890' appears in the Debug panel on the right side of the editor.

// Status

cooked. baked. worked.

A browser-based drag-and-drop automation editor running on your own machine, ready for you to wire together triggers, logic, and actions without writing any code.

// the honest bit

The honest part

Node-RED runs only while your terminal is open. If you restart your computer it will not start automatically unless you set it up as a background service — that requires extra steps not covered here. Node-RED has no built-in login or password by default, so anyone on your local network can access it. Do not expose port 1880 to the internet without first enabling authentication via the settings file. Complex integrations (MQTT, databases, cloud APIs) will need additional community nodes installed through the Manage Palette menu inside the editor.