Find the water filter that actually removes what's in your water.
We check your tap water against EPA records, then match you to filters independently certified to remove those exact contaminants — ranked by real cost, not by who pays us.
5,682 certified filters · 28 contaminants · EPA data for 19,092 water systems
Three steps to the right filter
See what's in your water
Enter your ZIP and get a plain-English report from EPA records — the contaminants found, and how the levels compare to federal limits.
Match to certified filters
We show only filters independently certified (NSF, WQA, IAPMO) to remove your specific contaminants — not marketing claims.
Buy the best value
Compare real cost per gallon — including replacement filters — so you don't overpay for the same clean water.
The cheap-looking filters cost the most
A $20 pitcher or fridge filter feels cheap — but per gallon of clean water it's often the most expensive option, because the cartridge runs out fast. A pricier under-sink or gravity system is far cheaper over time. We compute the real cost for every filter.
Compare real costs →Representative figures from our cost model (filter price ÷ certified capacity). Whole-house systems are lower still on a different basis.
Filters certified to remove…
"Tested to" isn't "certified"
Many brands say "tested to NSF Standard 53" without holding certification. We only count filters actually listed in the NSF, WQA, or IAPMO databases — and we flag the difference.
"NSF certified" isn't one thing
A filter certified for lead may do nothing for PFAS, arsenic, or fluoride. We list the exact certified claim for every filter so you know what you're actually getting.
Data decides, not dollars
Rankings come from independent certification and real cost per gallon — computed before any buy link. See our methodology.