Xiaomi’s air purifiers are among the most popular. In this article, I will compare the Xiaomi Mi 3H from the third series with the Xiaomi 4 Lite from the fourth series.
According to Xiaomi, the Mi 3H covers rooms up to 484 sq. ft. (45 m²), while the 4 Lite is designed for spaces up to 330 sq. ft. (31 m²).
Both air purifiers offer plenty of smart features, work with the Xiaomi Home app, and rank among the smartest models we’ve tested.
We analyzed their specifications and test results to determine which one is the better buy.
Our Verdict
In my opinion, whether you choose the Xiaomi Mi 3H or the Xiaomi 4 Lite, you can’t go wrong—both devices are highly efficient and well-built.
However, I would opt for the newer generation and go with the Xiaomi 4 Lite.
It performed slightly better in the smoke test, offers more advanced features, and has a better-optimized motor for noise reduction, which are key reasons why I’d choose this model.
If you have any questions about these two air purifiers, feel free to leave a comment below.
Specs: Xiaomi Mi 3H vs 4 Lite
| Product Image |  |  |
| Manufacturer | Xiaomi | Xiaomi |
| Model | Mi 3H | 4 Lite |
| Dimensions (inches / cm) | 9.5 x 9.5 x 20.5 inches (24 x 24 x 52 cm) | 9.4 x 9.4 x 21 inches (24 × 24 × 53.4 cm) |
| Weight (pounds / kg) | 10.6 lb (4.8 kg) | 10.6 lb (4.8 kg) |
| Clean Air Delivery Rate (CADR) | 223 CFM (380 m³/h) | 212 CFM (360 m³/h) |
| Coverage (4.8 ACH)
Room Coverage Explanation: ACH is a measurement used in indoor air quality management to indicate how many times the air within a defined space is changed/moved through the filter media.
For more details, visit our ACH calculator tool. | 484 sq. ft. (45 m²) | 330 sq. ft. (31 m²) |
| Performance Ratings Performance Ratings Score Summary: 8.4 - Average Score (79 products) 9.8 - Best Score (2 products) 2.5 - Worst Score (2 products) We use the Temtop LKC-1000S laser particle meter to test the particle removal efficiency of every air purifier. It measures PM2.5 (µg/m3), PM10 (µg/m3), Particles (per/L), and HCHO (mg/m3) in the air, and also calculates the AQI. You can read more about our testing methodology here. | ||
| Filtration Technology | Pre-filter, True HEPA and Active Carbon Filter | Pre-filter, Xiaomi's High Efficiency Filter, and Activated Carbon Filter |
| Filter Replacement Indicator | Yes | Yes |
| Filter Life | 6-12 months | up to 12 months |
| Power Consumption
Power Usage Summary: Our extensive testing of 79 air purifiers revealed the following power consumption insights:
Check out our power consumption calculator tool. | 38W | 33W |
| Operating Costs Ratings Operating Costs Ratings Score Summary: 9 - Average Score (79 products) 10 - Best Score (2 products) 1.7 - Worst Score (1 products) We measure the power usage at all speeds using an energy meter, after which we calculate how much it would cost to use the device at a particular fan speed for one month. For reference, we use an energy price of $0.12 per kWh. You can read more about our testing methodology here. | ||
| Number of Fan Speeds | 6 – Automatic Mode, Sleep Mode, Speed 1, Speed 2, Speed 3, and Manual Mode | 15 - Through Manual Mode |
| Air Quality Sensor Air Quality Sensor Summary: Out of 79 air purifiers tested, only 39 have the air quality sensor. | Yes | Yes |
| Air Quality Indicator | Yes | Yes |
| Auto Mode Auto Mode Summary: Out of 79 air purifiers tested, only 40 have auto mode functionality. | Yes | Yes |
| Smart App Smart App Summary: Out of 79 air purifiers tested, only 25 have smart app functionality. | Yes | Yes |
| Voice Control Voice Control Summary: Out of 79 air purifiers tested, only 24 have voice control functionality. | Yes | Yes |
| Other Features | Temperature and HumidityParental ControlsDisplay Off | Humidity & Temperature Sensor |
| Noise Level (low – high) | 40.9 – 65.4 dBA | 40.1 - 61.6 dBA |
| Noise Ratings Noise Ratings Score Summary: 9.3 - Average Score (79 products) 10 - Best Score (1 products) 8.2 - Worst Score (1 products) We use a special noise measurement tool to test the noise level of the air purifier at all speeds. We measured the noise level on the dBA scale. You can read more about our testing methodology here. | ||
| Best Suited For | Living Rooms Kitchens Offices Allergies Large Spaces Smart Home Integration | Living Rooms Bedrooms Offices Allergies Dust Smart Home Integration |
| Warranty | 1-year | 1-year |
| In-Depth Review | Xiaomi Mi 3H | Xiaomi 4 Lite |
| Price | Check Price on Amazon | Check Price on Amazon |
Performance Test – Comparison
Based on their recommended room coverage, we tested these two air purifiers in rooms of different sizes.
In the first test, we placed them in a 320 sq. ft. (30 m²) room, where both improved air quality by 95%.
Particle Removal Tests - Comparison
We placed the Xiaomi Mi 3H and Xiaomi 4 Lite in two separate tests and measured their performance using the Temtop laser particle meter.
In the second test, conducted in a 560 sq. ft. (52 m²) room, they again delivered identical results, improving air quality by 90%.
From these tests, we can easily conclude that both air purifiers performed equally well in removing airborne particles.
Smoke Box Test – Comparison
We compared the smoke neutralization performance of these two air purifiers in our smoke box test.
For this test, we placed each air purifier separately inside a glass box, filled the box with smoke, and let the purifiers run at maximum speed.
Despite being designed for smaller rooms, the Xiaomi 4 Lite cleared all the smoke in just 14 seconds, while the Xiaomi Mi 3H took 15 seconds.
This means the Xiaomi 4 Lite was about one second faster than the Xiaomi Mi 3H.
Noise Level Test – Comparison
Xiaomi has improved noise performance with its fourth-generation air purifiers.
The biggest change is that the Xiaomi 4 Lite offers fifteen fan speeds, compared to just six on the Xiaomi Mi 3H.
At the lowest speed, the Xiaomi Mi 3H produces 40.9 dBA of noise, while the Xiaomi 4 Lite is slightly quieter at 40.1 dBA.
Noise Level Comparison
Comparing the Xiaomi Mi 3H and Xiaomi 4 Lite noise levels at minimum and maximum speeds.
The difference is more noticeable at maximum speed, where the Xiaomi 4 Lite measures 61.6 dBA, compared to 65.4 dBA for the Xiaomi Mi 3H.
Not only does the Xiaomi 4 Lite offer more fan speed options, but it’s also better optimized for noise, making it quieter overall.
Operating Costs – Comparison
When it comes to operating costs, the first factor to compare is power consumption.
The Xiaomi 4 Lite runs on a 33W motor, while the Xiaomi Mi 3H has a slightly larger 38W motor.
If you were to run both air purifiers at maximum speed 24/7 for a month, your electricity bill would increase by approximately $3.25 for the Xiaomi 4 Lite and $3.42 for the Xiaomi Mi 3H.
Power Usage Comparison
Comparing the Xiaomi Mi 3H and Xiaomi 4 Lite power use at minimum and maximum speeds.
Beyond power consumption, there’s also the cost of replacement filters, which need to be changed about once per year in the case of both.
Since these two models use nearly identical power motors and filters with the same lifespan, their annual maintenance costs are essentially the same.
One thing to note, however, is that finding replacement filters for these models, especially in the US, can be a bit challenging.
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