Xiaomi has returned to India’s air-purifier market under its Mijia smart-home label, launching the Smart Air Purifier 4 Compact alongside the larger Air Purifier 6. The 4 Compact is the entry-level model, priced at ₹7,999, but it does not feel like a stripped-down appliance.
That price is its biggest advantage. It gives first-time buyers a fairly low-risk entry into air purification, and it also makes a room-by-room approach possible. A purifier in the bedroom and another in the study is usually more useful than asking one machine in the hallway to solve every air-quality problem in the house.
Mijia Smart Air Purifier 4 Compact Review: Design and Set-Up
Xiaomi has gone for function over flair with the Mijia Smart Air Purifier 4 Compact. It is a compact white cylinder with a black touch panel sitting on top, measuring 22cm across and 35.5cm high. At 2.2kg, it is easy to place on a desk, side table or floor, and light enough to move to another room when needed.
A handle would have made it more convenient to carry around the house, but the low weight keeps this from being a serious omission. This is not a purifier you will struggle to lift.
The setup is equally uncomplicated. Remove the protective cover from the filter, connect the power cable and switch it on. It can be used straight away through the top panel. Xiaomi Home takes a few more minutes to pair, but the app is useful for settings that are not available directly on the machine.
Air is pulled in through the perforated lower section and pushed out from the top. This makes the placement rules fairly obvious: keep the lower vents and upper grille clear. The purifier will still run if it is wedged against a wall, but it will not be operating at its best.
At the rear, there is an opening for the particulate matter sensor. It should be kept clean, since the sensor feeds the Auto Mode and helps the purifier decide when to increase fan speed.
The touch controls include power, light adjustment and mode selection. Auto, Sleep and Manual each have their own indicator, alongside status icons. The light strip gives a quick read on the air it detects: green for 0–35, yellow for 36–75, orange for 76–150 and red beyond 150. It is simple, visible and useful from across a room.
Mijia Smart Air Purifier 4 Compact Review: Filtration
The Mijia Smart Air Purifier 4 Compact uses a cylindrical filter that combines three layers. There is a pre-filter for larger particles such as hair and household dust, a HEPA filter for finer matter, and activated carbon for odours. Air is pulled in through the bottom vents, passes through those layers and exits from the top.
Xiaomi rates the filtration system at 99.97 per cent for particles down to 0.3 microns. Its list includes dust, pollen, smoke and pet dander, while TÜV Rheinland Allergy Care certification gives it an added allergy-focused credential. For people who wake up with itchy eyes or spend half the morning dusting a desk, those are the claims that matter most.
Its particle CADR is 230m³/h, and Xiaomi advertises coverage of more than 400 sq ft. The small print is important here: the coverage calculation assumes two air changes an hour. The purifier can therefore be used in a larger room, but its size and airflow make it a more convincing pick for a bedroom, small living room, study or personal office. That is where it can keep working through the room’s air at a more useful pace.
The activated carbon layer is the compromise. During an incense test, it made quick work of the visible smoke, but the fragrance stayed in the room much longer. The purifier is clearly better at removing particulate pollution than it is at clearing stubborn odours. Buyers who need help with smoke and pollen will be happier than those looking to neutralise heavy cooking smells.
Auto Mode is the sensible default. The onboard sensor responds to changing air quality and takes care of fan speed on its own. Sleep Mode switches off the display and is rated at 20dB. In everyday use, the purifier is quiet even outside Sleep Mode. With a ceiling fan on, I could not hear it from roughly two feet away.
Manual Mode lets you set the purifier’s speed through Xiaomi Home. You can select Manual on the device itself, but any adjustment to its level happens in the app.
Mijia Smart Air Purifier 4 Compact Review: App & Features
The Mijia Smart Air Purifier 4 Compact can be operated entirely from its top panel, so Xiaomi Home is optional. The app adds useful controls that make it more convenient.
Remote power control means you can start it before reaching home. You can also set timers, move between Auto, Sleep and Manual modes, and change display brightness. The child lock disables the buttons on the purifier, while notification sounds, device sharing, automation routines and firmware updates are also covered. Google Assistant and Amazon Alexa support are included too.
Manual Mode benefits most from the app. Xiaomi does not give you a row of numbered fan levels. Instead, you choose room coverage with a slider, and the purifier sets its speed to suit. Once saved, selecting Manual on the purifier brings that setting back without needing to open the app again.
Xiaomi Home does not present air-quality information particularly well. The purifier’s main page shows a broad “Good” status, which is reassuring but offers little detail. The home dashboard can display a particulate reading in µg/m³, though it is not carried through to the device page. There is no history chart either.
That makes Xiaomi Home useful for control and automation, but less helpful if you want to track how quickly the purifier has improved the room.
Mijia Smart Air Purifier 4 Compact Review: Living With It
The Mijia Smart Air Purifier 4 Compact works best in Auto Mode. Its sensor manages the fan, increasing speed when air quality worsens and reducing it once the room is back in shape. There is little reason to keep changing settings yourself.
Noise is one of its strengths. Xiaomi rates Sleep Mode at 20dB, and the purifier is quiet enough to keep beside a bed. You can also switch off the screen at night. Outside Sleep Mode, the fan is still well controlled. You will notice it at a higher speed, but it avoids the strained noise cheaper purifiers often make.
The 27W power rating makes it practical to leave running for long periods. Xiaomi estimates 24 hours of maximum-power use at roughly 0.7kWh. Everyday use on Auto should be lower again.
Changing the filter takes a minute. Twist open the base, slide the cylindrical cartridge out and fit a new one. Xiaomi Home gives filter-life reminders. The remaining question is replacement-filter cost and availability in India.
Mijia Smart Air Purifier 4 Compact Review: Verdict
The Mijia Smart Air Purifier 4 Compact is an easy first air purifier to recommend at ₹7,999. It is small enough to place almost anywhere, quiet enough for a bedroom, and happy to sit in Auto Mode while you get on with your day.
The three-layer filter, app controls and 27W rating make it more rounded than a basic budget purifier. It also suits homes that would rather use smaller purifiers in the rooms that need them than expect one large unit to handle everything.
The app does not show air-quality data particularly well, and the small carbon layer cannot tackle every strong smell. Filter cost and availability will matter over time, though Xiaomi says replacements will remain readily available during peak demand.
Those are manageable compromises. This is an affordable, quiet and capable way to bring cleaner air into the rooms you use most.
