Why it matters
The Blueair Blue Pure 121 Replacement Filter is a replacement filter for the Blueair Blue Pure 511.
Made for Blueair's Blue Pure 121 purifiers. The model label is usually on the back or under the filter door; match it before ordering.
Most purifier HEPA filters last six to twelve months in normal use; follow the unit's filter indicator and replace sooner in smoky or pet-heavy homes.
It fits the Blueair Blue Pure 511, which its maker lists as rated for 189 sq ft. A unit that runs on high in a large room loads its filter faster than the same unit on low in a bedroom.
Use the filter made for your exact unit: purifier filters seal against their own housing, and a close-but-different filter lets air bypass the media.
The listing gives dimensions of 2.5 x 13 x 18.2 inches.
Who it's for, and who should skip it
Good fit if
- Blueair Blue Pure 511 owners
- Keeping rated performance
Look elsewhere if
- Other purifier models
Pros and cons
Pros
- Exact-fit replacement
Cons
- Only fits its own unit family
- A recurring cost of owning the purifier
Limitations to weigh
- Specifications are the maker's or seller's own figures; check fit against your equipment's model number and the actual size.
Specifications
The bracket shows where each figure comes from.
| Model number | F121PACF101653 | Retailer |
|---|---|---|
| Dimensions (seller) | 2.5 x 13 x 18.2 inches | Retailer |
Alternatives worth comparing
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- Blueair Blue Pure 311i Max Allergenblock Filter $64.99
All air purifier replacement filters, compared in one table · Every Blueair product we cover
Final verdict
A well-matched choice for blueair Blue Pure 511 owners. Confirm the model it fits before ordering.
Where to buy
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