Poor ventilation in home offices and bedrooms often goes unnoticed until fatigue, brain fog, or headaches creep in during long work sessions. While traditional room thermometers tell you if a space is hot or cold, they offer no insight into air freshness. Xiaomi is tackling that specific frustration with its latest budget environment monitor, the Mijia Smart Temperature and Humidity Meter 3 Pro, which adds active carbon dioxide (CO2) monitoring alongside standard climate tracking.
Currently crowdfunding in China via Xiaomi Youpin for 114 yuan (approximately $17), the 3 Pro elevates Xiaomi's line of entry-level ambient sensors. By combining multi-sensor tracking with a clear visual readout and smart home integration, the new monitor aims to keep indoor air clean and circulating without requiring expensive HVAC overhauls.
A Larger Display for Comprehensive Air Monitoring
The primary upgrade in the Mijia Smart Temperature and Humidity Meter 3 Pro is its integrated CO2 detection system. Xiaomi selected a low-power sensor manufactured by Sensirion to measure carbon dioxide concentrations in real time. Rather than making users memorize safe parts-per-million (PPM) values, the device translates air quality into simple visual alerts using green, yellow, and red status indicators directly on the screen.
To accommodate this extra data, Xiaomi expanded the display footprint significantly. The 3 Pro features a 3.6-inch LCD panel, providing plenty of room to show the current time, date, day of the week, temperature, relative humidity, and CO2 level simultaneously. For context, the standard Mijia Monitor 3 utilizes a 2.5-inch panel, while the compact Mini 3 relies on a smaller 2.1-inch screen. Despite driving a larger screen and active gas sensing components, the 3 Pro runs on a single replaceable CR2450 coin cell battery, which Xiaomi estimates will last up to one full year under normal usage.
Smarter Automations via Bluetooth Mesh
Beyond functioning as a standalone desktop climate gauge, the Meter 3 Pro expands how user home environments respond to changing air conditions. Utilizing Xiaomi's Bluetooth Mesh system, the device connects to a compatible gateway to transmit readings directly to the Mi Home mobile application. Users can review historical trend charts over time to identify when air quality drops throughout the day.
More importantly, the inclusion of CO2 data enables sophisticated smart home triggers. While older models could only activate appliances based on temperature or humidity swings, the 3 Pro can automatically power on smart plugs connected to ventilation fans, open motorized windows, or spin up Xiaomi air purifiers as soon as ambient CO2 levels cross a custom threshold. This automated response helps clear out trapped indoor air before high gas concentrations affect sleep or focus.
Pricing and Market Availability
The Xiaomi Mijia Smart Temperature and Humidity Meter 3 Pro is presently available through Xiaomi's Youpin crowdfunding platform in China for 114 yuan (approx. $17). While global release details and official international pricing have not yet been announced, previous models in the lineup eventually made their way to global retail channels. Given Xiaomi's track record of expanding its smart home ecosystem worldwide, an international rollout is likely in the coming months.
