A practical identification checklist

Find the full air purifier model number before ordering a filter.

When a unit is second-hand, the label is worn, or the filter code looks unfamiliar, use this recovery path to find the right identifier without guessing from appearance.

Start with the line marked “Model” or “Model No.” Copy the full code, including letters, digits, hyphens, and suffixes. The appliance model, a serial number, and a filter part number answer different questions.

Know which number you are reading

Model / Model No.: identifies the purifier model. Preserve suffixes such as -P, -S, RAC, and Auto when printed.
Serial / S/N: identifies an individual unit. A normal filter lookup does not need the full serial. Use only a limited serial fragment when the manufacturer’s exact guidance asks for it, as in the narrow Coway Airmega 250 check.
Filter / Part / SKU: identifies a filter or set, not the purifier. You can search a readable OEM part code in the finder, but one part can be listed for several models.
Barcode, UPC/EAN, QR code, or MAC: may identify a product package, retailer item, or connected device. Do not substitute it for the model line.

If you cannot read or find the model label

Check the outside of the unit first. Look over its identification or rating label, including the rear, lower exterior, and sides. These are places to inspect, not a guarantee that every model puts its label there.
Keep the search safe. If you need to move or tilt the purifier, switch it off and unplug it first. Do not open a motor or electrical housing. Remove a grille or top section only when the manual for that exact model says to do so.
Search the maker’s manual library. If you know the brand or product family, use the official manual page below. A front-panel family name may help find the manual, but it is not enough by itself to confirm a filter.
Check your own purchase records. The original box, manual, receipt, or retailer order history may show the exact model. Compare it with the appliance label where possible.
If the label is missing or damaged, contact the maker directly. Give support the brand and what you can identify. If the manufacturer asks for a serial or label photo, send only what it requests through its official support channel. Do not post an unredacted serial, MAC address, or QR code publicly.

Manufacturer recovery pages

Label positions and access steps can differ by series. Follow only guidance that names your product family and region; these links help identify a model and do not establish filter fit, local stock, or delivery.

Blueair Blue Pure: its US support article gives separate label-finding steps for the listed cylindrical and square Blue Pure models. It says the model label may be under the top section or on the rear, depending on the unit. Do not carry those steps over to another Blueair series.
Blueair Classic and DustMagnet: use the separate Classic label guidance or DustMagnet label guidance. The Classic article says to unplug the unit before laying it on its side.
Levoit: search the official manual library by product name or model code.
Philips: use the official support model search with the complete model number, including its slash suffix. This is a model-recovery route, not a filter-fit statement.
WINIX: use WINIX America support if the model label or its filter path remains unclear. One public C535 owner described a long model sticker on the back and a separate bottom barcode/serial sticker; this is one owner report, not a locator rule for every WINIX model. Read the discussion.
Coway: start with the official product-manual library. Some model-specific filter checks require only a narrow serial fragment; follow the linked Coway instruction rather than sharing the full number.
Honeywell: use Honeywell air-purifier support and select the exact HPA model before following a manual’s access steps.
GermGuardian: the maker’s customer-care page links manuals and support options.
Dyson: choose the exact machine on Dyson air-treatment support. A serial-number locator is not a model-number lookup.

Common near-matches that should stay separate

Blue Pure 211+ and 211+ Auto. Blueair’s 211+ filter page explicitly excludes the 211+ Auto. Keep “Auto” when searching.
Levoit Core Mini-P and LV-H128. Levoit lists these as separate filter products; use the exact purifier model.
Coway AP-1512HH and AP-1512HHS. The HHS/MightyS suffix has its own filter-set listing. Do not match only on the shared AP-1512 prefix.
Levoit Core 300 family. The index keeps 300-P, 300S-P, P350-P, and 300-P-RAC separate because manufacturer pages list different variants for specific filter products.
Philips model suffixes. The shared FY2422/30 listing names four purifier families, but complete regional model codes may carry additional endings. Keep the full label in your records.
WINIX original 5500 and 5500-2. Keep the full suffix: original 5500 has separately listed Filter A, Filter G, and Pack P references, with a code discrepancy on the Filter G page. The 5500-2 manual names Filter H / 116130. For original 5500, check the installed-filter code or manual, or ask WINIX.

Search the source-linked model index ↗

Record scope: 50 source-linked model records across eight brands, with US, Canada, and UK manufacturer pages identified in the index, checked October 20, 2026. This is a limited sample, not a complete catalog. Similarity is not fit evidence.