Levoit Core 400S-P Review: A Sensor-Led HEPA Purifier for 360 sq ft

What the Core 400S-P is

The Core 400S-P keeps the cylinder layout of the smaller Core models: air is drawn in all the way around the base and blown out of the top. Inside is a three-stage filter (pre-filter, a main filter Levoit rates at 99.97% down to 0.3 microns, and an activated carbon layer). On top is a ring display that shows the PM2.5 reading from Levoit's AirSight Plus laser sensor and changes color with air quality.

The "S" means smart: it connects to Levoit's VeSync app for schedules, filter-life tracking and remote control, and works with Alexa and Google Assistant. The "-P" marks the current filter family; replacement filters for the 400S-P are listed by Levoit as compatible with the Core 400S-P only.

Levoit Core 400S AHAM numbers and room size

The AHAM Verifide directory lists two entries. The Core 400S is rated 231 cfm for smoke, 240 for dust and 259 for pollen, for a 358 sq ft room. The Core 400S-P (model LAP-C401S) is rated 234, 233 and 257, for 363 sq ft. The difference is within testing variation; either way, the smoke figure is about 60% higher than the Core 300's 143 cfm.

Air changes per hour from 231 cfm smoke CADR, 8 ft ceilings.

Room	Floor area	Air changes an hour
Main bedroom, 14 x 16 ft	224 sq ft	7.7
Living room, 15 x 20 ft	300 sq ft	5.8
AHAM room size	358 sq ft	4.8
Open plan, 20 x 25 ft	500 sq ft	3.5
Levoit's headline figure	1,718 sq ft	1.0

The 1,718 sq ft on the box assumes one air change an hour. For allergies, pets or smoke, plan on the AHAM figure or less. Our sizing calculator shows the numbers for your own room.

Sensor and Auto Mode

The main reason to pay for the 400S-P over the Core 300-P is the laser particle sensor. A laser sensor counts particles in a small sample of air, which is the same principle consumer air quality monitors use, so it reacts to cooking smoke, dust from cleaning and candle soot within seconds and raises the fan speed. It does not detect gases such as VOCs or carbon dioxide; the carbon layer handles some odors, but nothing on the machine measures them. Our guide to how air quality monitors work covers what each sensor type can and cannot see.

Noise, power and filter cost

Levoit lists a noise range of 22 to 52 dB and says Sleep Mode can run as low as 24 dB. The top speed is audible across a room but is lower than many tower purifiers of similar CADR. Levoit rates it at 38 W, which is low for its airflow; AHAM's directory puts its annual energy use at 237 kWh, with an integrated energy factor of 5.8, more than twice as efficient as the Core 300.

The replacement filter is $49.99 on Levoit's store, with Pet Allergy and Toxin Absorber versions at $59.99. Levoit's filter page does not print a replacement interval; the purifier and the app track filter life from run time. At one filter a year that is $49.99; at two, about $100, which is a realistic range for a unit running daily.

What the Core 400S-P costs to run for three years

Running cost is filters plus electricity. AHAM's directory estimates the Core 400S-P uses 237 kWh a year; at 17.2 cents per kWh, EIA's 2025 average US residential price, that is about $41 a year. Filters are $49.99 each from Levoit, and how many you need depends on how many hours a day it runs and how dusty the home is.

Three-year cost at Levoit's list price, AHAM's annual energy estimate and 17.2 cents per kWh. Our arithmetic.

Item	One filter a year	Two filters a year
Purifier (Levoit list price)	$219.99	$219.99
Filters, 3 years	$149.97	$299.94
Electricity, 3 years	$122	$122
Total	$492	$642

Electricity is the smaller share here because the Core 400S-P is efficient for its airflow. For a less efficient purifier of the same size the power bill can rival the filters, which is why AHAM's integrated energy factor is worth a glance when two models are close on CADR.

Core 400S-P vs the alternatives

AHAM Verifide figures, read November 3, 2026.

Model	Smoke CADR	AHAM room size	Notes
Levoit Core 400S-P	234 cfm	363 sq ft	Laser sensor, app, 38 W
Levoit Vital 200S-P	250 cfm	388 sq ft	Pet Mode, side inlet for hair
Winix 5510	253 cfm	392 sq ft	Larger carbon filter, PlasmaWave
Honeywell HPA300	300 cfm	465 sq ft	No sensor, louder, more airflow
Levoit Core 600S-P	394 cfm	611 sq ft	For open plan rooms

For a bigger room, the Honeywell HPA300 moves more air for similar money but has no sensor. For odors, the Winix 5510 has a thicker carbon filter.

Who should buy the Levoit Core 400S-P

• Buy it for a living room or main bedroom of 250 to 360 sq ft where you want Auto Mode to do the work.
• Buy it if efficiency matters: 38 W rated power for about 230 cfm is among the best in its class.
• Skip it for a small bedroom; a Core 300-P covers it for less.
• Skip it for heavy pet hair; the Vital 200S-P's extra inlet and Pet Mode are built for that.
• Skip it if you do not want an app account; the purifier works without one, but schedules and filter tracking live in the app.

More choices at this size are in our best air purifiers and best smart air purifiers guides.