Overview
Node-RED is an open-source tool for building event-driven applications by wiring together blocks called nodes in a visual editor that runs in your browser. Instead of writing all the glue code by hand, you drag nodes onto a canvas and connect them to define how messages flow between hardware devices, APIs, and online services.
It targets developers, makers, and integrators who need to connect systems quickly, and it is widely used for IoT and event-driven automation. The flows you build run on top of Node.js, and you can drop into JavaScript inside function nodes when you need custom logic.
As a low-code / no-code builder, Node-RED sits between full hand-written code and closed automation platforms. A large library of community nodes and shareable flows lets you extend the palette and reuse patterns instead of starting from scratch.
What it does
- Browser-based visual editor for wiring nodes into flows
- Built on Node.js, with function nodes for custom JavaScript logic
- Large community library of custom nodes and shareable flows at flows.nodered.org
- Well-suited to IoT, hardware, API, and online-service integration
- Runs locally, on servers, or on small devices like single-board computers
- Open-source under the Apache 2.0 license, maintained by the OpenJS Foundation
Getting started
Install Node-RED globally with npm, start it, and open the editor in your browser. See https://nodered.org/docs/getting-started/ for full instructions.
Install Node-RED
Install the package globally using npm.
sudo npm install -g --unsafe-perm node-redStart Node-RED
Run the node-red command to start the runtime and editor.
node-redOpen the editor
Open the visual flow editor in your browser, then drag and connect nodes to build a flow.
http://localhost:1880Commands and code are distilled from the project's own documentation — always check the official repo for the latest.
When to use it
- Wiring IoT sensors and hardware devices to dashboards or alerts
- Connecting APIs and online services together without writing all the glue code
- Building event-driven automations that react to incoming messages
- Prototyping integrations quickly before committing to a full code implementation
How Node-RED compares
Node-RED alongside other open-source low-code & no-code builders tools AI/TLDR tracks, ranked by GitHub stars.
| Tool | Stars | What it does |
|---|---|---|
| Langflow | ★ 150k | Langflow is an open-source platform for building AI agents and workflows visually, then deploying each flow as an API or MCP server. |
| NocoDB | ★ 63.5k | An open-source tool that turns any SQL database into a no-code spreadsheet-style app, used as a self-hosted Airtable alternative. |
| Flowise | ★ 53.7k | Flowise is an open-source low-code tool that lets you build LLM apps and AI agents by connecting nodes on a visual canvas, then ship them as an API or chat widget. |
| Appsmith | ★ 40.1k | An open-source low-code platform for quickly building internal tools, admin panels, and dashboards from a visual editor plus custom JavaScript and data-source connections. |
| ToolJet | ★ 38k | An open-source low-code platform with a drag-and-drop UI builder, built-in database, and JavaScript logic for building internal tools, dashboards, and workflows. |
| Directus | ★ 36k | An open-source data platform that wraps any SQL database in an instant API and a no-code admin app for managing content and building back-office tools. |
| Refine | ★ 34.9k | A React meta-framework for building data-heavy internal tools, admin panels, dashboards, and B2B apps, combining low-code generators with full code control. |
| Node-RED | ★ 23.3k | Low-code, flow-based programming for event-driven and IoT applications |