Blueair Blue 511i Max Smart WiFi Air Purifier, HEPASilent Dual Filtration Up To 43m², Whisper Quiet, Air Cleaner for Pets, Allergies, Virus, Dust, Mould, Smoke

Easily one of my best purchases of 2025. After using it for a short time, it genuinely makes you wonder how you ever lived without an air purifier. The air quality improvement is noticeable, especially in a bedroom environment. The room feels fresher and less stuffy, and it has helped significantly with dust and general air cleanliness. The app functionality is excellent, simple to set up, responsive, and useful for monitoring air quality and adjusting settings remotely. The unit itself is fairly large, but this clearly comes down to the size of the filter, which inspires confidence rather than being a negative. It feels well built and designed to handle larger rooms properly rather than being underpowered. Noise levels are impressively low. Even when running continuously overnight, it is quiet enough not to disturb sleep, which was a major deciding factor for me. Overall, a very effective, well designed air purifier that delivers exactly what it promises. Highly recommended for anyone considering improving their indoor air quality.

Seems ok, and phone app is useful. I've been using this for approx one month now and the phone app connected to this device is super useful to check on the current 'air quality' level as well as viewing how much of the filter is 'left' until it is recommended to be changed. My air quality is generally good or excellent on most days, and there is still (after one full month, 90% left) of my filter for use. So, it isn't working hard and you can probably get 10 months or 12 (if you push it) per year with each filter. Operationally, usage is very quiet, which is solid plus.

Just started using it in my bedroom and I can already feel the difference. The air feels lighter and cleaner, and it’s super quiet — perfect for sleeping. Easy to set up and looks nice too. So far, very happy with it

It appears to work as per all the claims. I put it in the main bedroom because the house is 1900’s with a wooden floor and I was convinced that dust was coming up from the floor. The unit quickly told me that the air quality was great and there were no issues. The only time it moves to mid speed is when sorting laundry or changing the bed (cotton lint dust) so I know it works. The app is a good way to visualise the use and auto mode takes care of things. I’ve struggled to get the top indicator lights to dim completely at night which is a pain - and I’m kinda disappointed that it finds little issue in the room so I’m not really benefiting from the unit.

Great product. Had it around 2 months now and I'm shocked at the amount of dust this thing has filtered out the air. I bought this as I wake up with a blocked nose and a feeling like I've been tickled with a feather in my nose. Was dubious that this would make a difference but I was at my whits end so gave in, bought it and now wouldn't sleep without it on. Ease of use: Being able to store it behind my tv and be able to control it by the app is such a great thing. Easy to use, press the power button and it comes on, slide the fan speed and it changes quickly and an easy button press for night mode that you can barely hear

Works perfectly fine. Connectivity from app to air purifier could be improved. Makes the air feel cleaner. Has helped with morning allergies. App includes useful information such as when the filter needs changing. Not very loud on fan 1 and 2 but is quite noisy on fan 3. I have found the schedule feature helpful.

Could tell air was better eighin 1 hour

I used to have a blueair 211, the square one which worked fairly well for about 4yrs until it started making a high pitched whine and the fan blades were clogged with dust with no way to get in there to clean it. So I bought this one. Very lightweight but also had an annoying high pitched sound from the start especially noticable on the first speed. I quickly noticed within days this is useless at keeping dust at bay. My surfaces were thick in a few days whereas my 211 had kept it down despite running on a low speed all the time and this one at speed 2. I suspect the thicker prefilter on this may be the suspect. My nose was still stuffy all the time unlike with the 211. Whenever I needed to reboot my router this purifier would not connect with the app meaning I had to delete it and reset it up again. There's no way to just reconnect in the app itself. At the 3 month mark it refused to connect with the app, it also started having power problems. Suddenly and repeatedly the fan speed would stop for a few seconds with a flashing white light then come back on again. Thankfully Amazon were fabulous and let me return for a refund. I will be purchasing a different brand and I doubt I'll be coming back to blueair anytime soon.