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Choosing the right temperature and humidity sensor for Home Assistant can be a tricky task. After all, there are so many to choose from. Before deciding which one to with you should ask yourself a few questions: Does the sensor have to be battery-powered, or can it be mains-powered? What ecosystem am I already using? Do I need extra features such as a screen to display the data gathered from the sensors?

Say for example, you already have a bunch of Zigbee lights and use ZHA, Zigbee2MQTT or deCONZ. Then the obvious answer would be to go with Zigbee sensors. You will be hard-pressed to find a Zigbee sensor that isn’t battery-powered so that question will answer itself. If you want to use one of the many Xiaomi Bluetooth Low Energy sensors, which have an e-paper display, you will need an ESP32 to add the readings to Home Assistant. So keep in mind that certain setups will be more complicated than others.

Being able to measure the temperature and humidity is one of the most basic things you will want to do in a smart home. This metric can be useful in a number of ways: You can use the humidity to detect whether someone is the bath or shower and thus keep the lights on. If you live in a dry area you might turn on a humidifier when the humidity reaches a certain percentage, or you can use the temperature to adjust a thermostat. And some people, like me, just like seeing nice graphs on their Home Assistant dashboard.

Below you will find a selection of highly rated temperature and humidity sensors which are all compatible with Home Assistant. Some sensors will require a hub or an extra device to connect to, so make sure you have everything you need, before purchasing.

Aqara Temperature and Humidity Sensor (Zigbee)

The tiny temperature and humidity sensor from Aqara is powered by a single CR2032 coin cell battery which can keep it running for up to two years. They work from -20 ℃ (-4℉) to 50 °C (122℉) with an accuracy of ±0.3℃ (±0.5°F), which is pretty good.

When bought directly from China, the Aqara Temperature and Humidity Sensor can be had for a very low price. These sensors are also reasonably good at measuring the humidity of a room with an accuracy of ±3%. Though not advertised in the sensors name, they can also measure atmospheric pressure.

One thing to note is that the Aqara Temperature and Humidity Sensor won’t be continuously reporting to your Zigbee adapter. Instead, it will cleverly conserve power by only reporting once the value change reaches a certain threshold. Yet, I have found the Aqara Temperature and Humidity Sensor to react rather quickly when the shower being used.

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Aqara Temperature and Humidity Sensor, REQUIRES AQARA HUB, Zigbee, for Remote Monitoring and Home...
  • ✽【NOTES】Aqara Hub is required and sold separately. Requires a secured 2. 4 gigahertz WiFi network connection. One Aqara Hub can connect up to 32 Aqara devices.
  • 【REMOTE MONITORING】When the room temperature reaches above or below a certain threshold, the Aqara Temperature and Humidity Sensor can send a push alert to your phone or trigger the Aqara Hub night light.

There is some confusion surrounding the Aqara brand. You will often see it described as Xiaomi Aqara. Before Lumi United, which is Aqara’s parent company, created its own line of smart home products under the brand name Aqara they were making devices for Xiaomi’s smart home brand called Mi and sometimes also Mijia. Many of the Mijia and Aqara sensors look and behave similarly because they are essentially the same device. Due to this relationship, you will often find Aqara devices described as Xiaomi Aqara devices.

You will also be able to find a Mijia/Mi temperature and humidity sensor which looks just like a round version of the Aqara equivalent. In comparison to the Aqara Temperature and Humidity Sensor, the Mijia/Mi sensor is missing one feature: It doesn’t measure atmospheric pressure. Additionally, I prefer the square look of the Aqara sensor and that is why they are my primary recommendation.

The Aqara temperature and humidity sensors
The Aqara temperature and humidity sensors
The Mijia/Mi temperature and humidity sensors
The Mijia/Mi temperature and humidity sensors
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These sensors use the Zigbee protocol and thus need a compatible hub or a DIY Zigbee receiver. I use the excellent open-source project Zigbee2MQTT for all of my Zigbee sensors and lights. Zigbee2MQTT allows me to use just about every Zigbee device without having to buy multiple hubs. For more information you can read through my guides on the subject.

At a glance

Aqara Temperature and Humidity Sensor

Sensors: Temperature, humidity, and atmospheric pressure

Technology: Zigbee

Form factor: Square, with rounded corners

Battery: CR2032

At a glance

Mijia/Mi Temperature and Humidity Sensor

Sensors: Temperature and humidity

Technology: Zigbee

Form factor: Round

Battery: CR2032

Philips Hue motion sensors

Did you know that the Philips Hue motion sensor, which just as the previous two sensors also use the Zigbee protocol, has a hidden temperature sensor? Well, now you do. And if you already have a few of these sensors placed around your home, you may as well use them to their maximum advantage.

To be able to access the temperature in the Philips Hue motion sensor you will either need a Hue Labs Formula or the sensor has to be connected to a DIY Zigbee application such as Zigbee2MQTT. Unfortunately, the hidden temperature sensor is all there is. The Philips Hue motion sensors do not measure humidity.

Xiaomi Bluetooth Low Energy sensors

Xiaomi produces a number of Bluetooth Low Energy (BLE) sensors, which come in all kind of shapes and sizes. These have the added bonus of having a screen which will display the current temperature and humidity. A few of them use e-paper displays which I very much like the look off. By using an e-paper display, the time, temperature, and humidity is legible even when the sun is out.

HiLetgo ESP-WROOM-32 ESP32 ESP-32S Development Board 2.4GHz Dual-Mode WiFi + Bluetooth Dual Cores...
  • 2.4GHz Dual Mode WiFi + Bluetooth Development Board
  • Ultra-Low power consumption, works perfectly with the Arduino IDE

Getting BLE sensors integrated with Home Assistant used to be quite a tricky task. But thankfully ESPHome has largely solved that issue. Using the Xiaomi BLE component you can connect these temperature and humidity sensors to an ESP32 using only a few lines of YAML. You won’t need to do any soldering as the bare ESP32 and an old phone charger is all that you need. Despite the setup being easier, some beginners might still struggle with it.

If you’re looking for a temperature and humidity sensor which has a screen and connects to Home Assistant, the Xiaomi BLE sensors are the way to go. Because the ESP32 is dirt cheap you won’t have to pay too much extra to get these to work nicely with Home Assistant.

The XIAOMI LYWSD03MMC temperature and humidity sensor

Xiaomi LYWSD03MMC

Sensors: Temperature and humidity

Design: Square

Technology: BLE

Display: Segment LCD

The XIAOMI CGG1 temperature and humidity sensor

Xiaomi CGG1

Sensors: Temperature and humidity

Design: Round

Technology: BLE

Display: E-paper

The XIAOMI LYWSD02 temperature and humidity sensor

Xiaomi LYWSD02

Sensors: Temperature and humidity

Design: Rectangular

Technology: BLE

Display: E-paper

The XIAOMI JQJCY01YM temperature and humidity sensor

Xiaomi JQJCY01YM

Sensors: Temperature, humidity, and Honeywell formaldehyde

Design: Rectangular

Technology: BLE

Display: Segment LCD

Shelly H&T (Wi-Fi)

If you don’t want or a have a Zigbee hub and keep all your sensors connected via Wi-Fi, the Shelly H&T might be for you. The Shelly H&T is considerably bigger than the Aqara sensors because Wi-Fi is a lot more power-hungry than Zigbee. On battery, the Shelly H&T will last about 16 months, but it can also be powered with a USB power supply, making it more flexible than other sensors.

Shelly H&T Humidity and Temperature Wireless Smart Sensor Compact WiFi Hygrometer Monitor Home...
  • [ Humidity ] Monitor excessive changes in humidity. Avoid dryness and conditions for mold growth. Humidity measurement range – 0~100% (±5%)
  • [ Temperature ] Be aware of temperature fluctuations and keep your home comfortable at any time

Personally, I don’t like the design of this sensor. Wi-Fi needs more power in comparison to Zigbee and BLE, so there’s no way the Shelly H&T could run for an extended period on a single coin-cell battery. It looks big and bulky in comparison to the Aqara sensors I use. Those can be hidden away on a bathroom cabinet or stuck to the wall. The Shelly H&T will take some skill to hide.

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But if you do require a Wi-Fi temperature and humidity sensor, the Shelly H&T is your best bet. It is also the way to go if you are seeking continuous updates from the sensor. When connect to the mains, the Shelly H&T doesn’t require any power-saving.

DIY humidity and temperature sensors

And finally, you have the option of building your sensors. Grab yourself an ESP8266 or ESP32 board and a BME260 temperature sensor, and you will be good to go. Thanks to ESPHome, the code for a custom sensor is written and compiled in next to no time.

HiLetgo 3pcs ESP8266 NodeMCU CP2102 ESP-12E Development Board Open Source Serial Module Works Great...
  • ESP8266 CP2102 NodeMCU LUA ESP-12E WIFI Serial Wireless Module
  • Built-in Micro-USB, with flash and reset switches, easy to program

Building your sensors can be a fun project and is certainly more rewarding than just opening a cardboard box and pushing a button to get the sensor connected. Just keep in mind that ESPHome isn’t best suited for battery-powered devices, and it might take some tinkering to get things working perfectly. Examples of makers building battery-powered are to be found, which might inspire you.

A DIY temperature and humidity sensor powered by ESPHome it will more than likely have to be powered from the wall. On the bright side, this does allow for continuous recording. And because you are using ESPHome you aren’t restricted to just using adding one sensor. You could also hook up more sensors, attach some LEDs, or use it for presence detection.

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If you do want to go down the DIY route I have an article on why the BME280 is currently the best temperature and humidity for your DIY electronics projects. Whatever you do, do not cheap out and go for the DHT11. I promise you will regret it. You can also get yourself a BME680 if you want to be able to measure air quality too.

At a glance

BME280

Sensors: Temperatures, humidity, atmospheric pressure

Cost: ~$2

At a glance

BME680

Sensors: Temperatures, humidity, atmospheric pressure, gas resistance

Cost: ~$6

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About Liam Alexander Colman

Liam Alexander Colman has been using Home Assistant for various projects for quite some time. What started of with a Raspberry Pi quickly became three Raspberry Pis and eventually a full-blown server. I now use Unraid as my operating system and Home Assistant happily runs in a Docker container. My personal setup includes many Zigbee devices as well as integrations with existing products such as my Android TV box. Read on to find out more on how I got started with Home Assistant.

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