SwitchBot Motion and Presence Sensors for Smart Room Automation

Best for
Lights on when you walk in

The SwitchBot Smart Motion Door Sensor is a classic PIR motion detector. PIR sensors react to changes in infrared heat as a warm body moves across their field of view, which makes them quick and reliable at spotting someone entering a room. SwitchBot lists a detection range of up to almost 30 feet, covering 110° horizontally and 55° vertically, and you can tune the sensitivity so it only alerts you to the movement you care about.

It runs on two AAA batteries, included, with an average battery life of three years according to the listing, and it mounts on a wall. The spec sheet also lists a maximum range of 393 feet; the listing does not explain this figure, and it is far beyond the stated 30-foot detection range, so treat it as a wireless figure rather than how far it sees motion. The small body measures about 2.1 by 1.2 by 2.1 inches.

Automation happens through Scenes in the SwitchBot app. The listing’s example is that when you come home, a SwitchBot Bot button pusher turns on the light, and Alexa greets you. It can also switch lights off when it detects the room is empty. Remote alerts and Alexa compatibility need a SwitchBot Hub. For a gaming room, it is ideal at the doorway to fire up LED strips and a monitor scene as you walk in. The trade-off is the one every PIR sensor shares: if you sit very still for long stretches, it may decide the room is empty. That is where the mmWave model takes over.

• PIR detection up to about 30 feet
• 110° horizontal and 55° vertical field
• Adjustable sensitivity
• Two AAA batteries included, around three years of life

Best for
Gamers who sit still for hours

The SwitchBot Smart mmWave Radar Motion Sensor is a presence sensor. It combines millimeter-wave radar with light sensing and a PIR sensor, and SwitchBot says it can pick up the subtle chest movements of a person who is not moving otherwise. In general terms, mmWave radar sends out low-power radio signals and measures tiny changes in the reflections, which lets it register breathing where a PIR sensor would see nothing change. For anyone who games, streams or reads for hours, it is the fix for lights that switch off when you stop moving.

Coverage is 120° wide, with a range of up to 8 meters for moving people and 5 meters for stationary people. The listing mentions dynamic detection and zone positioning, and the magnetic base lets you lay it flat, mount it on a wall and adjust its angle to aim the detection zone. An AI self-learning mode, enabled with one click, filters out interference from fans and air conditioners, which matters in a room with a PC blowing warm air and a desk fan running. It uses a built-in battery that can run up to two years on a charge.

Platform support is the broadest of the three. The listing names Apple Home through the SwitchBot Matter Hub, Home Assistant, Alexa and Google Home. If you want presence detection in HomeKit, note that it needs that Matter hub. This is the sensor to put on your desk shelf or behind the monitor, aimed at your chair. The one thing it does not replace is a door sensor for entry alerts.

• mmWave radar plus PIR and light sensing
• 120° field, 8 m moving and 5 m stationary range
• AI filtering of fans and air conditioners
• Magnetic, adjustable base

Best for
Doors, windows and room entry scenes

The SwitchBot Door Alarm Contact Sensor- Smart listing is a pack of three contact sensors. Each one detects doors and windows opening and closing, but SwitchBot adds two extras: a built-in motion sensor and a light sensor. The motion sensor lets it tell whether you are leaving or coming home, so different Scenes can fire for each, and the light sensor can trigger a SwitchBot Bot to turn a light on when someone moves through a dark space.

Installation is tool-free, the sensors are small and wireless with long battery life, and each weighs about 49 grams. The listing gives a 30-foot sensing distance. SwitchBot suggests uses beyond doors, like a medicine box or a pet cage. With a SwitchBot Hub, you get door-open alerts on your phone while away, and Alexa can sound a voice alarm. Another example Scene turns off an air purifier through a SwitchBot Bot when a window opens.

For a gaming room, a contact sensor on the door is the cleanest trigger for “someone just walked in” and makes a reliable partner to a presence sensor. It is not built to tell whether you are still sitting in the room, so do not use it as your only lighting trigger. If you are building out your setup with physical controls too, a wireless 3-way switch can sit alongside these for manual overrides.

• Three sensors in the pack
• Door and window open and close detection
• Built-in motion and light sensors
• Tool-free installation