Methodology

1. Manufacturer sources only. A match needs the brand’s own filter page, product page, compatibility chart, manual or support page. Retailer listings can help us find models, never prove a fit.
2. Exact model, exact market. Each record is one model in one market (US for now). A Canadian “CA” model is a separate record.
3. No inference. If the manufacturer doesn’t name a model, we don’t list it — even when it looks identical to one that is named.
4. Quoted evidence. Every verified page shows the quote, the page it came from, where on the page, and the date we checked.
5. Part numbers need their own proof. If a brand shows two different part numbers, we show neither.
6. Conflicts stay unresolved. Unresolved pages are hidden from search engines, left out of the sitemap, and never show a buy button.
7. Intervals and quantities only when official. We don’t estimate how often to replace a filter.

Spotted something wrong? Email hello@purifierfilterfinder.com with the model and a link to the manufacturer page.