What is Zigbee?
Zigbee is a wireless communication technology used by many smart-home devices, including sensors, smart plugs, switches, lighting controls and heating devices.
It is designed particularly well for networks containing lots of relatively low-power devices that need to communicate small amounts of information reliably.
One of Zigbee’s most useful features is its ability to create a mesh network, where compatible routing devices can pass Zigbee messages between each other instead of every device needing a direct connection to the hub.
Zigbee in simple terms.
Think of a Zigbee network as a small wireless network created specifically for compatible smart-home devices.
Instead of every sensor, plug and switch connecting directly to your home’s Wi-Fi router, Zigbee devices join a Zigbee network managed by a coordinator.
1. Coordinator
Creates and manages the Zigbee network. This is commonly built into a smart-home hub or provided by a dedicated Zigbee coordinator.
2. Routers
Compatible Zigbee router devices can pass messages between other devices and help extend the mesh across the home.
3. End Devices
Devices such as battery-powered temperature, door and motion sensors commonly operate as end devices. They communicate through the network but normally do not route messages for other devices.
What is a Zigbee mesh network?
A mesh network allows compatible Zigbee routers to relay messages through the network.
This means a device does not necessarily need a strong direct wireless connection to the coordinator. Its message may be able to travel through one or more Zigbee routers before reaching its destination.
A simple example
Imagine your Zigbee coordinator is downstairs, but you have a sensor upstairs at the opposite side of the house.
A compatible Zigbee router positioned between them may provide another route through the mesh, helping the network reach devices that would otherwise have a weak direct connection.
Many permanently powered Zigbee products can operate as routers, but this depends on the individual device. Being mains-powered does not by itself guarantee that a particular Zigbee product will route messages.
What is a Zigbee hub or coordinator?
Every Zigbee network needs a coordinator. The coordinator creates and manages the Zigbee network and allows devices to join it.
In many consumer smart-home systems, the coordinator is built into a device commonly described as a Zigbee hub, bridge or gateway.
More advanced smart-home systems may instead use a dedicated USB or network-connected Zigbee coordinator with software such as Home Assistant.
The important distinction is that a Zigbee device does not normally connect directly to your home’s Wi-Fi network. It joins the Zigbee network created by the coordinator.
Zigbee vs Wi-Fi.
Zigbee and Wi-Fi can both be used in a smart home, but they are designed for different types of communication. Neither technology is automatically better for every situation.
Designed for device networks
- Usually requires a Zigbee coordinator
- Well suited to low-power sensors
- Can form a mesh using compatible router devices
- Allows many smart-home devices to operate on a separate network from normal Wi-Fi clients
- Commonly used for sensors, plugs, switches, lighting and controls
Direct IP connectivity
- Devices commonly connect directly to your Wi-Fi network
- Usually does not require a separate Zigbee-style coordinator
- Suitable for devices requiring greater network bandwidth
- Commonly used by cameras, speakers and other higher-bandwidth devices
- Large numbers of smart devices add additional clients to the home’s Wi-Fi infrastructure
Many smart homes use both technologies: Wi-Fi for devices that benefit from direct IP connectivity or higher bandwidth, and Zigbee for sensors, switches and other automation-focused devices.
What devices use Zigbee?
Zigbee is used across a wide range of smart-home products.
Sensors
Temperature and humidity sensors, motion sensors, presence sensors, door and window contacts and water-leak sensors.
Smart Plugs
Control compatible appliances and lamps, create schedules and use other devices as automation triggers.
Lighting
Smart bulbs, lighting controllers and compatible switching devices can form part of a Zigbee lighting system.
Switches & Modules
Compatible switches, relays and in-wall modules can add smart control to existing electrical circuits.
Heating
Compatible thermostats, radiator valves and environmental sensors can provide room-by-room monitoring and control.
Buttons & Controls
Wireless buttons and scene controllers can trigger automations without requiring a phone or voice assistant.
Does every Zigbee device work together?
No. This is one of the most important things to understand when building a Zigbee smart home.
Two products carrying the Zigbee name are not automatically guaranteed to expose every feature when used together.
Actual compatibility can depend on the coordinator or hub, software platform, device model, firmware and whether the platform supports the particular functions exposed by the device.
Zigbee does not mean universal compatibility
Before purchasing a Zigbee device, check that the specific device is supported by the hub, coordinator or smart-home platform you intend to use.
Does Zigbee need the internet?
Zigbee itself is the communication network between Zigbee devices and the coordinator, so the underlying Zigbee radio network is not the same thing as an internet connection.
However, whether your smart-home system continues to provide app control, remote access, automations or other features without internet access depends on the hub and software platform you are using.
Some systems process more functions locally, while others depend on cloud services for particular features.
Can Zigbee work with Home Assistant, Alexa and other platforms?
Yes, Zigbee devices can be used with many different smart-home ecosystems, but the method and level of support depend on the hardware and platform involved.
Home Assistant
Home Assistant can be used with compatible Zigbee coordinators and integrations. Device support and available features depend on the coordinator, integration and individual Zigbee device.
Alexa & other ecosystems
Zigbee devices may be exposed to voice assistants and other smart-home ecosystems through compatible hubs, integrations or platform connections. Support varies between products and systems.
Always check compatibility before purchasing. A device being described as Zigbee does not by itself guarantee that every feature will be available through your chosen platform.
How do you build a good Zigbee network?
A Zigbee network can start small and expand over time.
Choose your coordinator
Select a Zigbee hub or coordinator that supports the smart-home platform and devices you intend to use.
Add your first devices
Pair your initial sensors, plugs or controls and confirm that they communicate reliably in their intended locations.
Build out the mesh
Where necessary, compatible Zigbee router devices can provide additional routes through the network and improve coverage.
Expand gradually
Add devices room by room, checking compatibility and network performance as the system develops.
Why is Zigbee useful for home automation?
Home automation becomes much more useful when devices can respond to events around the home rather than simply being controlled from an app.
A door sensor can trigger another device when a door opens. A temperature sensor can provide the condition for a heating or ventilation routine. A motion sensor can trigger lighting. A wireless button can start several actions at once.
Zigbee provides the communication network that allows compatible devices to participate in these kinds of automations.
Want to learn more about Zigbee?
Zigbee is maintained as part of the standards and technologies developed by the Connectivity Standards Alliance. Their official Zigbee information provides further technical background.