Levoit PlasmaPro 400S Smart True HEPA Air Purifier

If you’re on a tight budget and have a small space to address, this purifier—with its slight footprint and powerful HEPA filter—is a great option. If you want any additional features, like the ability to monitor your air quality or set timers, however, you’ll need to consider a more expensive model. From a technical standpoint, the only major flaw we found with this purifier is that there’s no definitive way to know if it’s working. We tested the purifier in a bedroom with two people and a shedding Bassett hound, running it overnight for a week. Following our initial run, we turned it off for a few nights to compare the difference in air quality. While we didn’t notice any significant difference during the week it was running, we could certainly tell during the off-days that the unit had indeed been doing its job when it was on.
That feature allows you to set the machine to an automatic mode, in which it adjusts its speed depending on the air quality in the room. Many air purifiers, including relatively compact air purifiers, can provide clean air for a large room, but the coverage area of each air purifier does vary. Be sure to review the listed coverage area before completing your air purifier purchase. The main drawback of the Levoit air purifier is that it has no auto feature or display indicating current air quality.
This unit is not equally efficient as the larger Levoit models but it does its job. The Molekule Air Mini+ is designed for small spaces, like a bedroom or home office. In our testing, it performed far worse than our pick for those scenarios, the Levoit Core 300—which costs about $100, versus the Air Mini+’s typical $350 or more.
On the low setting, it produced 52 decibels; while much quieter, it was still noticeable. This machine does have a sleep setting which produced a noise that was all but unnoticeable and dimmed the display lights. The Levoit Core 300 stands out for having excellent air-purifying capabilities, particularly for its size. It offers some of the most customizable programing options of any of the models we tested and even includes a sleep mode.
On medium, running around the clock, they consume only about $6 worth of electricity per year. Replacement filters cost $19, and if you stick to the six-month replacement schedule, they add up to just $171 (nine filters) over the course of five years. The total five-year running costs are thus just $200, about 60% less than the costs of the Levoit Core 300. Add in the Blue Pure 411 models’ quiet operation and good looks, and they are an attractive option for small spaces.
Each of the units has been put through it’s paces during our real-world testing, without bias as we never accept free products, making our reviews 100% independent. Levoit air purifiers are not without problems so be sure to also look at our troubleshooting levoit air purifier guide that will help you

levoit filter

fix most issues that face these purifiers. Our previous top pick among large-space purifiers, the Coway Airmega 400, is a stellar performer, registering 99.9% and 99.7% reduction of particulates on high and medium, respectively, on both new filters and filters that had been run 24/7 for a year.
Ionizers impart an electrical charge to air molecules that pass through the machine. These ionized air molecules then in theory bind to airborne particles and give them a charge, encouraging them to stick together and to create larger particles that may be easier to filter or large enough to settle out of the air. Most purifiers with an ionizer let you toggle the feature on or off, and we recommend off.