Coway Airmega 150 vs Coway Airmega 400S
103 facts in comparison
Based on 564 Reddit opinions. Airmega 400SCoway Airmega 400S leads by 10 points.
564 opinions
Airmega 400S leads by 10pts
VS
CA
Airmega 150
77%
B
Based on
526 Redditors
Coway Airmega 150
~$151.99
290 opinions
tldr; The bedroom workhorse. True HEPA, 214 sq ft coverage, whisper-quiet at 22dB. Best small-room value.
Check pricesVS
Reddit's Pick
CA
Airmega 400S
87%
A-
Based on
521 Redditors
Winner
Coway Airmega 400S
~$649.99
274 opinions
tldr; Large room workhorse. Handles wildfire smoke. Wait for sales (~$350). Side intake - won't fit in corners.
Check prices💨FIL
⭐ROO
🔇NOI
⭐FIL
🔧BUI
73
Points
72
Points
Score by Category
Filtration Performance
76%86%
Room Coverage
55%85%
Noise Level
66%61%
Filter Replacement
74%50%
Build Quality
89%79%
Why is Coway Airmega 400S better than Coway Airmega 150?
- Higher Reddit score (87% vs 77%)
- Better filtration (86% vs 76%)
- Better coverage (85% vs 55%)
- Ideal for 700+ sq ft open layouts
- Excels at wildfire smoke removal
- Wait for sales - often hits $350
Based on 1,047 Reddit opinions
Slight Edge
Reddit prefers the Airmega 400SCoway Airmega 400S
Winning by 10 points (87% vs 77%)
Better filtration
Better coverage
Ideal for 700+ sq ft open layouts
High confidence (1,047 mentions)
💬Reddit Sentiment
Based on 1,047 Reddit mentionsOverall Rating
Airmega 150
7.7/10
526 mentions
Airmega 400S
8.7/10
521 mentions
COVERAGE
Airmega 1505.5/10
Airmega 400S8.5/10
FILTRATION
Airmega 1507.6/10
Airmega 400S8.6/10
FILTER COST
Airmega 1507.4/10
Airmega 400S5.0/10
VALUE
Airmega 1507.7/10
Airmega 400S6.8/10
BUILD QUALITY
Airmega 1508.9/10
Airmega 400S7.9/10
NOISE
Airmega 1506.6/10
Airmega 400S6.1/10
⚔️
Head to Head
| Topic | Airmega 150 | Airmega 400S |
|---|---|---|
Coverage | 55% | 85% |
Filtration | 76% | 86% |
Filter Cost | 74% | 50% |
Value | 77% | 68% |
Build Quality | 89% | 79% |
Noise | 66% | 61% |
Category Wins
Airmega 150: 4|Airmega 400S: 2
Head to Head
Airmega 150: 4|Airmega 400S: 2
CoverageAirmega 400S
Airmega 15055%
Airmega 400S85%
FiltrationAirmega 400S
Airmega 15076%
Airmega 400S86%
Filter CostAirmega 150
Airmega 15074%
Airmega 400S50%
ValueAirmega 150
Airmega 15077%
Airmega 400S68%
Build QualityAirmega 150
Airmega 15089%
Airmega 400S79%
NoiseAirmega 150
Airmega 15066%
Airmega 400S61%
Airmega 150
77%
87%
Airmega 400S
Airmega 15077%
Airmega 400S87%
Airmega 400S wins by 10 points
Key Specs
| Spec | Coway Airmega 150 | Coway Airmega 400S |
|---|---|---|
| Room Coverage | 230 sq ft | — |
| CADR | 152.8 CFM (259.6 m³/h) | — |
| Filtration System | Pre-filter, Carbon Filter, True HEPA Filter | — |
| Noise Level | 20 dB (minimum) to 52 dB (maximum) | — |
| Power Consumption | 35W | — |
Key Highlights
Coway Airmega 150
🔇 22dB sleep mode - near silent
📏 214 sq ft coverage
🌬️ True HEPA filtration
💰 Under $100 on sale
⏱️ 12-month filter life
Coway Airmega 400SWinner
🏠 Ideal for 700+ sq ft open layouts
🔥 Excels at wildfire smoke removal
💰 Wait for sales - often hits $350
⇄ Side air intake - needs wall clearance
🧹 Mini-fridge size but worth it
Topic Battles
Airmega 150: 3|Tied: 0|Airmega 400S: 2
💨Filtration Performance
Airmega 400S winsAirmega 150
76%
Airmega 400S
86%
⭐Room Coverage
Airmega 400S winsAirmega 150
55%
Airmega 400S
85%
🔇Noise Level
Airmega 150 winsAirmega 150
66%
Airmega 400S
61%
⭐Filter Replacement
Airmega 150 winsAirmega 150
74%
Airmega 400S
50%
🔧Build Quality
Airmega 150 winsAirmega 150
89%
Airmega 400S
79%
Based on Reddit sentiment across 5 categories
📈Where They Rank
💬What Redditors Actually Say
What Redditors Say
Best praise vs top criticism for Coway Airmega 400S
Best Praise
+6 pts“Coway purifiers are top notch. i have an AirMega 400 model in the room where we keep our cat litter boxes. it's built like a tank and after a year, it still showed the filters at maybe 75% remaining. i replaced them anyway, as i know the carbon pellets were spent without a doubt, and wanted to combat litter box smells... but the filters were still in fine shape. Coway filters are like $80, but i found a review / test of third-party filters that didn't have any appreciable difference for $30. they make a bunch of different sized purifiers for different room sizes, so see what suits your sit.”
r/AirQuality
ViewTop Criticism
+6 pts“This is infuriating. I bought the 400 thinking it would be the best option to keep the air clean for my baby and now I come to find out that I could possibly be doing more harm then good? Im trying really hard to remain calm right now.”
r/AirPurifiers
View3 more quotes available below
What Redditors Say
Best praise vs top criticism for Coway Airmega 150
Best Praise
+12 pts“The [Coway Airmega 150](https://cowaymega.com/products/airmega-150) has a separate permanent pre-filter. This makes cleaning the pre-filter much easier and doesn't risk damaging the pleated HEPA media underneath. Airmega 150 also has higher CADRs. FYI: on Coway's website, the discount codes **COWAYMEGA10** or **FORYOU10** give an additional 10% off for the Airmega 150, which brings the price down to $122.40.”
r/AirPurifiers
ViewTop Criticism
+3 pts“So the bad news here is that the AirMega 150 moves around half the air of the other two. It has no onboard ionizer (which many consider a good thing), and it has green-HEPA medical grade filter with antimicrobial properties, so that's a plus, but it DOES move less air. It's quieter and looks nicer, but the CADR doesn't lie. In this case I'd advise to get the Levoit. I'm NOT a Levoit fan - in fact, I think they're generally a garbage company. But in this case it's CHEAPER, moves more air, has quite a good HEPA filter, and a carbon grid (which neither of the Coway models here do). HOWEVER, turn off the stupid smart features and cover the light when you get it. The air quality meter is a lie, the smart features just make it work worse. Turn it on, leave it on, and it'll be fine.”
r/AirPurifiers
View3 more quotes available below
Sentiment Over Time
Coway Airmega 150
Coway Airmega 400S
📈Historical Price Data
Coway Airmega 150
Coway Airmega 400S
Coway Airmega 150
All-time low: $124.99(2025-06)
$17 below 90-day avg
Coway Airmega 400S
All-time low: $358(2023-06)
Which is Better?
Coway Airmega 400S Wins
87%
400S
vs
77%
150
Coway Airmega 400S leads by 10 points based on 1,047 Reddit opinions.
Why Airmega 400SWinner
- 🏠 Ideal for 700+ sq ft open layouts
- 🔥 Excels at wildfire smoke removal
- 💰 Wait for sales - often hits $350
Why Airmega 150
- Better Value for Money (77% vs 68%)
❤️The Love/Hate Breakdown
Sentiment Breakdown
46%Positive
Positive
46%Neutral
48%Negative
6%Based on 521 Reddit opinions
Sentiment Breakdown
43%Positive
Positive
43%Neutral
45%Negative
12%Based on 526 Reddit opinions
Frequently Asked Questions
Which is better, Coway Airmega 400S or Coway Airmega 150?
Based on 1,047 Reddit comments, Coway Airmega 400S is the preferred choice with 87% positive sentiment vs Coway Airmega 150's 77%. Coway Airmega 400S leads by 10 percentage points.
Should I buy Coway Airmega 400S or Coway Airmega 150?
If you want the safer choice based on community sentiment, Coway Airmega 400S has stronger approval ratings (87% vs 77%). However, Coway Airmega 150 may still be better depending on your specific needs, budget, or use case.
What do Redditors love about Coway Airmega 400S?
Reddit users highlight: Ideal for 700+ sq ft open layouts. Excels at wildfire smoke removal. Wait for sales - often hits $350. With 521 mentions and 87% approval, it's a well-regarded choice in the community.
What do Redditors say about Coway Airmega 150?
Reddit users highlight: 22dB sleep mode - near silent. 214 sq ft coverage. True HEPA filtration. With 526 mentions and 77% approval, it remains a popular alternative.
How many Reddit reviews were analyzed?
This comparison analyzed 1,047 Reddit comments: 521 about Coway Airmega 400S and 526 about Coway Airmega 150. Data was sourced from Air Purifiers community discussions.
How accurate are these ratings?
Our sentiment analysis is approximately 80-85% accurate compared to manual review. Well-discussed products with many mentions tend to have more reliable scores than niche items with fewer data points.
Why trust Reddit over professional reviews?
Reddit users bought products with their own money and have no incentive to mislead. You're seeing hundreds of real opinions across different use cases, not just one reviewer's take. This crowdsourced approach surfaces both common praise and recurring complaints.
564 Reddit opinions analyzed · Last updated 4/30/2026