Z-Wave vs. ZigBee

A short smart home refresher course before we start: A smart home or home automation system is a collection of home devices that work together to provide useful functions such as automation and interoperability. The backbone of such systems is the wireless standard used to interconnect the devices. For the better part of the 21st century, those wireless standards have been either Z-Wave or Zigbee, though Matter is rapidly emerging as a unifying standard.

You can think of Z-Wave and Zigbee as languages. When two devices speak the same language, they can connect and work with each other. That’s the building block of every smart home. So if you’re trying to make your home smart, the first step is to decide which smart home language to use. That is, you have to choose between Z-Wave and Zigbee.

We’ll help you make that decision by breaking down how these two wireless standards stack up in real-world applications. After testing dozens of devices using both protocols, we’ve found that your choice often comes down to your specific setup needs: Zigbee excels in dense device environments with its unlimited hop capability, while Z-Wave shines when you need guaranteed compatibility between different brands.

Z-Wave

According to the Z-Wave Alliance’s data, over 100 million Z-Wave devices are now deployed worldwide, with more than 4,500 certified products available from 700+ manufacturers.1 This proprietary technology, now owned by Silicon Labs, requires a license for companies to incorporate in their products. While this licensing model ensures strict compatibility standards, it does mean manufacturers pay royalty fees to use Z-Wave, which can add to device costs.

Z-Wave devices are region-specific due to varying frequency regulations. American Z-Wave products operate at 908.4 MHz and won’t work with European devices that use 868.4 MHz. Both are low on the frequency spectrum, so Z-Wave devices don’t interfere with Wi-Fi networks. They may, however, interfere with some cordless phones that also work on low-frequency radio bands.

ZigBee

ZigBee is an open-source protocol maintained by the Connectivity Standards Alliance (formerly the Zigbee Alliance), which now boasts over 500 member companies.2 This open approach has led to widespread adoption, with estimates suggesting over 500 million Zigbee devices deployed globally. The fact that the same alliance now oversees both Zigbee and Matter protocols positions Zigbee well for future integration with the emerging Matter standard.

ZigBee uses the IEEE 802.15.4 radiofrequency. It also can use 915 MHz in the United States but the limitations on data, 40 kbps maximum, makes it inefficient at this frequency. The 2.4 GHz frequency is also available to ZigBee. However, using this frequency may cause interference with Wi-Fi networks.

While Zigbee and Wi-Fi both can operate on 2.4 GHz, they serve completely different purposes in your smart home ecosystem. Zigbee creates a mesh network specifically for smart devices to communicate with minimal power consumption, while Wi-Fi connects your devices to the internet with much higher bandwidth. Think of Zigbee as the internal nervous system of your smart home, while Wi-Fi is its connection to the outside world.

Encryption

Both Z-Wave and Zigbee use AES-128 symmetric encryption as their security foundation. This encryption standard scrambles data using a 128-bit key, making it difficult for hackers to intercept and decode your device commands. While there have been reports of certain Z-Wave and Zigbee products being hackable in the past, those are isolated cases. In fact, the most famous case was the Z-Shave vulnerability discovered in 2018, and it wasn’t actually a Z-Wave vulnerability. It was an issue caused by how the manufacturer implemented Z-Wave in its smart locks.

Both protocols have continued to strengthen their security, too. Z-Wave introduced Security 2 (S2) framework, which adds an extra layer of authentication, while Zigbee 3.0 includes improved security features like install codes and trust center link keys. Neither protocol has experienced any major security breaches in recent years.

Speed

ZigBee is significantly faster than Z-Wave. It transmits data at 250 kbps compared to Z-Wave’s transmission rate of 100 kbps. To put this in perspective, Zigbee can send a command to turn on your lights in about 20 milliseconds, while Z-Wave takes roughly 50 milliseconds. While both are fast enough that you won’t notice the difference in everyday use, Zigbee’s extra speed becomes valuable when you’re running complex automation scenes involving multiple devices simultaneously.

Compatibility

Z-Wave stands out in this area. Every Z-Wave Plus certified device is guaranteed to work with every other Z-Wave Plus device, regardless of manufacturer. This interoperability is enforced through mandatory certification testing. With over 4,500 certified products available, you can mix and match brands without worry.

Zigbee’s story is more complicated. Not all Zigbee-certified products on the market play nicely together. Some manufacturers create their own Zigbee implementations (like Philips Hue or IKEA TRÅDFRI) that may require their specific hubs or have limited compatibility with other Zigbee devices. However, devices certified for Zigbee 3.0 (introduced in 2016) offer much better cross-compatibility than earlier versions.

Range and Costs

Even though ZigBee is faster and cheaper, since it is not proprietary like Z-Wave, one of the drawbacks is the range. ZigBee has a range of 35 feet whereas Z-Wave can transmit and receive at up to 100 feet.

This is somewhat mitigated by the ability of both protocols to mesh. If you have more than one ZigBee or Z-Wave device within close proximity, it will act as a repeater or booster and allow the signal to go further.

Zigbee supports unlimited hops in its mesh network, while Z-Wave Plus is limited to four hops. Imagine you have a detached garage 200 feet from your house where you want to install a smart lock. With Zigbee, you could place devices every 30 feet and the signal would hop from device to device all the way to the garage. With Z-Wave, even though each hop can go 100 feet, you’d max out at 400 feet total (four hops) from your hub.

This makes Zigbee particularly attractive for large properties or commercial installations where you might need to cover expansive areas with many devices. However, for typical homes under 3,000 square feet, Z-Wave’s superior range per device often means you’ll need fewer repeaters to achieve full coverage.

Global Standard

Since ZigBee is an open-source protocol, Zigbee devices can theoretically work globally as they all use the 2.4 GHz frequency band that’s available worldwide. However, the reality is more nuanced.

This does not necessarily mean interoperability. Any manufacturer can use ZigBee for free and when they do so, they often use software that is incompatible with another brand.

Z-Wave takes a different approach. While it’s proprietary and requires licensing through Silicon Labs, this control ensures that any Z-Wave Plus device can communicate with any other Z-Wave Plus device from any manufacturer. The trade-off is that Z-Wave devices are region-locked due to different frequency regulations – a device bought in the US won’t work in Europe, and vice versa.

Final Thoughts

Both smart home device control protocols have certain advantages and disadvantages. It appears as though no one protocol has won the right to be called the standard. Z-Wave or ZigBee may ultimately win, but there are many other protocols developed or under development that may have more robust or attractive features that ultimately will push them to the top spot.