# Coway Airmega 400S

> On October 15, 2026 the lowest price for the Coway Airmega 400S is $749 at Coway (brand store), shipping to the United States included. In our ranking it is rank 9 of 9 for open-plan spaces, with a score of 5.0 out of 10.

- Page: https://bestatbest.com/us/air-purifiers/coway-airmega-400s
- Rank 9 of 9 for open-plan spaces in our ranking, score 5.0 out of 10
- Today’s lowest price: $749 at Coway (brand store), including shipping, checked on October 15, 2026
- Lowest since Oct 14: $749

## Our score

- Score 5.0 out of 10
- Lab tests, 60% of the score: no lab has tested it.
- Owners’ ratings, 25%: none yet at the stores that ship to the United States, so this part is left out and the others count for more.
- Features, 15%: 5.0, 32 of the 64 points for the facts the maker states.
- Price does not count, so a discount never lifts a model. Only robots a lab has tested are ranked.

## Prices per store

| Store | Color | Price | Delivery time | Checked |
|---|---|---|---|---|
| Coway (brand store) | gray | $749 | 3–7 days | 20 hours ago |
| Coway (brand store) | white | $749 | 3–7 days | 20 hours ago |

## Frequently asked questions about the Coway Airmega 400S

**What size of room is the Coway Airmega 400S for?**

The Coway Airmega 400S is sized for a room of about 499 ft², the room size we compare it on. Its clean air delivery rate (CADR) is 328 cfm.

**How often does the Coway Airmega 400S need a new filter?**

The maker gives the filter a life of 6 months.

**How loud is the Coway Airmega 400S?**

The maker states 22 dB at the lowest speed and 52 dB at the highest.

**Is the Coway Airmega 400S good for wildfire smoke?**

Its CADR for smoke is 328 cfm. A higher number clears smoke from a room faster, so compare it with the size of your room.


## The maker: Coway

- https://www.cowaymega.com/

Coway began in Korea in 1989 and describes itself as a global company with three decades focused on health. In the United States it sells Airmega air purifiers, Bidetmega bidet toilet seats and Aquamega water purifiers.

https://www.cowaymega.com/pages/about-coway

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