Certified Filter Fit

How we verify

Last updated

Every filter page is built the same way. Here's the process, so you can judge how far to trust each page.

1. Fit comes from the manufacturer, and nowhere else

  • A fridge model goes on a filter page only if a manufacturer source names it, such as the brand's product page, support article, filter chart or installation document. Each model list links to its source.
  • We never assume a fit from a similar model number. Fridge model numbers that differ by one character often take different filters. LG's own chart, for example, assigns different filters to closely related model numbers. If a model isn't in the source, it isn't on our list.
  • We copy model numbers exactly as the source prints them. If a source looks like it contains a typo (say, the letter O instead of a zero), we copy it as printed and mark it Unverified.
  • If a source is regional (a Canadian page, for example), we say so and point you to the manufacturer's US filter finder.
  • Retailer "fits these models" lists and other aftermarket fit claims are not used as fit sources.

2. Certification comes from the certifier's own listing

  • Claims on a box or product page ("certified", "tested to", "meets") are treated as claims. We check them against the certifier's public listing, usually NSF's Drinking Water Treatment Units listings. NSF itself says its listings "are the only way to ensure that a specific manufacturer and/or model is currently NSF certified".
  • We report the exact model a listing covers and the standards it's listed under (NSF/ANSI 42, 53, 401 and so on). Variants from the same brand can differ.
  • If we can't find a listing for a claim, we show the claim with an Unverified label. We don't call it false, because a listing can exist under a part number we didn't try.

3. How we use NSF's listings

NSF's terms of use don't allow commercial copying or reposting of its content. They also prohibit data extraction or data mining without NSF's prior written permission, and using NSF's marks without consent. So:

  • We link to NSF's live search results rather than copying them.
  • We summarize a small number of facts that we checked by hand (model, standards, sometimes capacity) for the specific filter a page is about.
  • We don't bulk-download, scrape or republish NSF's database, and we don't display NSF's logo or certification mark.
  • Listings change daily. Always open the linked NSF record before buying.

4. Every claim is cited

  • Every fact is followed by a source marker like [S1] that links to the source list at the bottom of the page. The list gives the publisher, a link and the date we accessed it.
  • Replacement and reset steps come from the manufacturer's own instructions, and we link to them.
  • Each page shows a "Verified on" date: the last day we re-checked every source on it.

5. What we leave out

  • Anything we couldn't confirm from a primary source is either left out or clearly labeled Unverified.
  • We don't publish star ratings, "best" awards or testimonials. We haven't lab-tested these filters ourselves.
  • We don't make health claims beyond what a certifier's listing states.

6. Re-checking

We re-check pages when a manufacturer changes a part number or a listing changes, and on a rolling schedule. When a page is re-checked, its "Verified on" date is updated. Spotted something out of date? Email [email protected].