We recommend the Coway AP-1512 HH Mighty as the best overall air purifier. It has great performance considering its price and offers a large number of filters including a HEPA filter, a pre-filter, an ionizer and an odor filter. It's also quiet to use, which is especially important if you want to use it at night. In Auto (similar to medium; the air does not contain a particle counter to adjust to air conditions, but instead asks you to enter the approximate size of your room, after which the machine chooses a fan speed that Molekule deems appropriate), the air performed worse, reducing particles by 0.3 microns at only 18.0% (ambient) and 26.4% (clean).
In Silent, it performed even worse, reducing 0.3 micron particles by 6.5% (ambient) and 7.2% (clean). And in Dark plus Auto, with its primary PECO purification system turned off and its fan at the equivalent of a medium setting, it reduced them by 21.3% (ambient) and 18.0% (clean). Interestingly, those numbers closely reflect our results in automatic configuration with the PECO system activated, suggesting the possibility that the Molekule Air depends mainly on its physical prefilter, not its patented PECO mechanism, to remove particles. The Levoit air purifier is also a great choice and is a Good Housekeeping seal holder due to its combination of value, performance and intelligent design.
It has a three-stage filtration system that includes a true HEPA filter which helps capture even the smallest airborne contaminants in rooms up to approximately 400 square feet. A built-in precision laser sensor accurately monitors particles in the room and automatically adjusts fan speeds as needed. The purifier is also incredibly quiet, it works at only 24 dB, which you will appreciate if it is placed in your bedroom. Additionally, it has intelligent capabilities such as the Levoit app which allows you to monitor air quality in real time, view filter life, and set schedules.
If you want an air purifier for a medium-sized room, the Coway HEPA air purifier is one of the best air purifiers with one of the most adventurous looks. The Blueair Blue Pure 411 is a simple and straightforward purifier with a smart design and a good investment. You get particulate and carbon filtration (activated carbon filter removes odors, pet dander, airborne allergens, and airborne gaseous contaminants) that will work well in a 160 square foot room, making it the best overall air purifier for rooms small. Some devices, such as the Sharp air purifier, don't even offer as much cleaning power at almost double the price.
If you have the money and want a super-powered air purifier or if you prefer a purifier to cover your entire house than buy one for each room, then the Coway Airmega 400 could be the best air purifier for you. This thing costs a dime but you get 1,560 square foot air cleaning coverage. It's also important to note that many of the best air purifier models have been going in and out of stock in recent months due to high demand during the pandemic and wildfires. The best air purifier looks elegant enough to fit modern decor, can work as desired with minimal manipulation, and can clean the air thoroughly and quietly.
Most of these devices contain something called a high-efficiency particulate absorption (HEPA) filter which can remove 99.97% of air pollutants 0.3 microns in size making them ideal for removing most indoor air pollutants such as dust particles which have a size of around five microns or pollen which has a size of 10 to 1000 microns. It is important to note that it is impossible to remove all particles that can live on walls, carpets, bedding and hard surfaces but an effective air purifier will remove different types of particles from the air while neutralizing unpleasant things in your home such as dust, odors, pet dander, smoke, bacteria and viruses. For context on our recommendations for the best air purifier options we considered power for price (i.e., higher CADR and lower price), additional cleaning modes, usefulness of controls, overall design and noise level.