The Levoit Core 400S is a mid-range air purifier with a three-stage filtration system. It's larger than the Levoit Core 300S and uses a more powerful motor. It boasts a similar range of automation features, with a built-in air quality sensor, smartphone app integration, and compatibility with Amazon Alexa and Google Assistant devices, allowing you to change settings with voice commands.
Our Verdict
The Levoit 400S air purifier is an excellent fit for pet owners. It's effective in trapping finer particles like pet dander, and you can use its companion app to have it run while you're away from home. That being said, it's a little louder than some alternatives, with a somewhat higher-pitched tone than other Levoit Core models, which is far from ideal if your pet is sensitive to louder noises.
- Wide assortment of convenience features.
- Excellent overall filtration performance.
- Companion app integration.
- Noisy at higher fan speeds.
- Somewhat large footprint.
The Levoit 400S is very good for bedrooms. It features a 'Display Off' function, so there are no bright lights you need to cover. While it's a little loud at higher fan speeds, with a slightly higher-pitched tone than alternatives, it's thankfully much quieter at lower speeds. It also offers amazing overall filtration performance. It's fairly large, and you can't rest it on a shelf or dresser.
- Wide assortment of convenience features.
- Excellent overall filtration performance.
- Display light shutoff.
- Companion app integration.
- Noisy at higher fan speeds.
- Somewhat large footprint.
- Wide assortment of convenience features.
- Excellent overall filtration performance.
- Companion app integration.
- Noisy at higher fan speeds.
- Somewhat large footprint.
- Wide assortment of convenience features.
- Excellent overall filtration performance.
- Companion app integration.
- Noisy at higher fan speeds.
- Somewhat large footprint.
Changelog
- Updated Jun 18, 2026: We've updated this review to Test Bench 1.3, which adds a new 'Footprint' test that's meant to score an air purifier's dimensions. If you're interested in learning more about why we made this change, read our changelog article.
- Updated May 01, 2026: We've updated this review to version 1.2 of our test bench. This new methodology adds the new Low-Noise Particle Filtration Rate test, which measures particle filtration performance when the device is configured to run at a standard operating volume below 45 dBA. If you're interested in seeing more about the changes made to this test bench, see our changelog.
- Updated Feb 20, 2026: Version 1.1 of our air purifier testing methodology provides a more representative summary of unit performance, with a revised Particle Filtration Rate test conducted in a better-sealed environment and a more reliable means of generating consistently sized particulate matter. We've also included a parameter for the machine's maximum recommended room size. For a more detailed breakdown of the changes made, see our full changelog.
- Updated Nov 04, 2025: Version 1.0.2 of our Air Purifier Test Bench rectifies calculation errors in our existing Particle Filtration Rate test to provide more representative results of some units. For a more detailed breakdown of the changes made, see our full changelog.
Check Price
Differences Between Sizes And Variants
This air purifier is available in three color variants: 'Black,' 'Gray,' and 'White.' We tested the 'Black' model.
Let us know in the comments if you come across another variant.
Popular Air Purifier Comparisons
This is a mid-range air purifier with a three-stage filtration system. The Core 400S is a better option than the cheaper Levoit Core 300S in most ways; while it has a much bigger overall footprint, it's far more effective in larger areas and boasts a similar range of convenience features. Its somewhat high-pitched operating noise can be annoying, especially when running the device at higher fan speeds.
The Levoit Core 400S and Levoit Vital 200S are somewhat evenly matched machines, though we'd give the edge to the Vital 200S for most uses. Both deliver near-identical air purification performance and offer a similar suite of smart features, including app connectivity, automatic fan adjustment, and voice control support. However, only the Vital 200S has a washable pre-filter and a U-shaped air inlet that's intended to resist clogs from pet hair, making it a more practical choice for homes with shedding pets. It also operates a little more quietly than the Core 400S, particularly at higher fan speeds, which can make it easier to live with in bedrooms and other frequently occupied spaces.
If the Levoit Core 300S feels a little too small for your needs, the Levoit Core 400S is the natural next step. Both purifiers share a similar set of convenience features, including app connectivity, voice control, automatic fan adjustment, and remote scheduling, but the 400S delivers substantially stronger air-cleaning performance thanks to its larger size and more powerful motor. That makes it a much better fit for larger bedrooms, living rooms, and open-concept spaces where the 300S can start to struggle. The tradeoff is a considerably larger footprint and a higher price tag, which is what makes the 300S the more practical choice when the smaller size is actually an advantage.
Test Results
The ring of lights around the power button changes color based on current air quality:
- Blue: Very good
- Green: Good
- Yellow: Moderate
- Red: Bad
Tapping the 'Display Off' button turns off all of the device's indicator lights and the night light. On that subject, the night light features two levels of brightness.
The VeSync companion app also allows you to remotely adjust the fan speed, set operating schedules, and send filter replacement reminders. It also can be used to view a real-time estimate of air quality.
This air purifier has a three-stage filter system comprised of a pre-filter for trapping larger airborne particles, a primary filter for trapping dust and mold particles, and an Activated Carbon filter for minimizing odors. You'll only need to clean the pre-filter with a soft-bristle dusting brush or a vacuum every two to four weeks, but make sure not to damage any other parts of the filter system when doing so.
You'll need to replace this filter assembly every six to eight months, and you can find a replacement here.
