Rank #3 in Best Air Purifier 2026: 10 Ranked on Real Air Changes
Bosch Air 4000 Air Purifier, CADR 300 m3/h, 3-in-1 Filter, 62.5 m2
Price and rating as shown on Amazon when we collected them. Both change.
The Air 4000 is the appliance-brand option here, and the listing is precise about filtration: a HEPA filter with a pre-filter and an activated carbon layer, quoted at a CADR of 300 cubic metres per hour for rooms up to 62.5 square metres, with a 25 decibel noise figure, 178 watts of draw and touch and app control, in a 5.8 kilogram white body.
That 178 watt figure is the standout number, and not in a good way: it is the highest power draw in this ranking by a wide margin, which matters if the purifier runs all day. A sleep mode and a smart sensor are named. At the time of collection it carried 711 ratings at 4.6 stars. Everything here comes from the Amazon listing rather than our own testing.
How those 711 ratings break down
An average hides its own shape. This is the spread behind the 4.6 stars.
Specification
Exactly as published on the Amazon listing, field for field.
| Power Source | Electric |
|---|---|
| Control Method | App |
| Filter Type | HEPA filter with pre-filter and activated carbon filter |
| Floor Area | 62 Square Meters |
| Noise Level | 25 Decibels |
| Particle Retention Size | 2.5 Micron |
| Controller Type | Touch control |
| Wattage | 178 watts |
| Contaminant Filtration Capability | dust, pollen, viruses |
| Special Features | HEPA filter, smart sensor, sleep mode |
| Filter Class | HEPA |
| Item Dimensions D x W x H | 29.1D x 29.1W x 50H centimetres |
| Item Weight | 5.8 kg |
| Colour | White |
| Brand Name | Bosch Thermotechnik |
| Model Number | 7733701943. |
| Number of Packs | 1 |
| Item Highlight | With 3-in-1 Air Filter, Smart Sensor, Auto Mode, Quiet Mode (< 25 dB(A)), CADR: 300 m³/h |
| Unit Count | 1.0 count |
| Manufacturer | Bosch Thermotechnik GmbH |
What buyers actually say
Quoted from customer reviews on Amazon
Verified purchase“works well and easy to set up tells you how much ppm pollutants are in the air . lightweight and not to noisy . air quality improved”
Verified purchase“I received this air purifier a couple days ago,so it's to early to say any details except that it work great,very simple to manage the function.”
What it is up against
The rivals it was ranked against in Best Air Purifier 2026: 10 Ranked on Real Air Changes.
Rank #1
Winix 5500-2 Air Purifier, CADR 390 m3/h, 4-Stage Filtration, PlasmaWave
£159.00
Rank #2
Levoit Core 300S Smart HEPA Air Purifier, CADR 258 m3/h, PM2.5 Sensor
£149.99
Rank #4
Coway Airmega Jet HEPA Air Purifier, CADR 402 m3/h, Allergy UK Approved
£279.99
Rank #5
Blueair Blue Max 3250i Smart WiFi Air Purifier, HEPASilent, Quiet Mark
£129.00
Questions people ask
What CADR is listed?
300 cubic metres per hour.
What filter does it use?
A 3-in-1 HEPA filter with pre-filter and activated carbon.
What room size is listed?
Up to 62.5 square metres.
What is the listed power draw?
178 watts, the highest in this ranking.
How many ratings does it have?
711 at the time of collection, averaging 4.6 stars.
Comments
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