Between the 5500-2 and C909, the 5500-2 comes out ahead in several specs, while the C909 wins on coverage and cadr. Overall, the 5500-2 scores 56.9 and the C909 scores 66.8 on our Mars Score.
Which should you buy?
The C909 is the clear pick on raw spec strength, leading by 9.9 points on the Mars Score. The margin is wide enough that the underdog only makes sense if its individual strengths line up with what you specifically need.
The 5500-2 doesn't pull ahead on any single popular-comparison spec — its strengths sit in the spec table groups rather than the headline advantages.
Pick the C909 if you care most about coverage and cadr. Its strongest claims are coverage, cadr, true hepa h13+.
Both ship with comparable activated carbon, min noise, so those specs don't separate the two — focus on the differences below.
Bottom line: the C909 is the safer default. The other model is the right choice only when its specific advantages line up with your priorities.
Why Winix - 5500-2 wins
- No decisive advantages.
Why Winix - C909 wins
- ▲Coverage — 51.52% more. 50 m² vs 33 m².
- ▲CADR — 20.48% more. 500 m³/h vs 415 m³/h.
- ▲Has True HEPA H13+.
Spec comparison
Performance
| Spec | Winix - 5500-2 | Winix - C909 |
|---|---|---|
| CADR | 415 m³/h | 500 m³/hlead |
| Coverage | 33 m² | 50 m²lead |
| True HEPA H13+ | false | truelead |
| Activated carbon | true | true |
Smart & Noise
| Spec | Winix - 5500-2 | Winix - C909 |
|---|---|---|
| Min noise | 27 dB | 27 dB |
| Air quality sensor | true | true |
| Smart app | false | truelead |
Frequently asked
Spec-level deep dives
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