Skip to content

AI Shelf Index

Which water filter brands do AI engines recommend?

We asked OpenAI, Perplexity and Claude, each through its API with web search, 20 questions a shopper might ask about water filters, 3 times each, on Nov 9, 2026. This page counts the brands the 180 completed answers named and the sites they cited.

· Water filters

20
buyer questions
3
engines, each through its API with web search
3
runs of every question on every engine
180
completed answers, each one read and counted

About these counts

  • These are answers from each engine's API, not a record of what every shopper sees in consumer apps. Answers change over time, so this page is dated.
  • The order is a count of answers, not a rating or an endorsement. We don't test products, and no brand paid to be listed.
  • We show counts and cited sites only, never claims about products.

Brands the answers named

Share of the 180 completed answers that named each brand, with each engine's count. Retailers and marketplaces are left out. When one engine gave at least three quarters of a brand's answers (5 or more), its row says so.

  1. 1Aquasana38% (68)

    OpenAI 19 / Perplexity 21 / Claude 28

  2. 2Waterdrop26% (46)

    OpenAI 7 / Perplexity 8 / Claude 31

  3. 3AquaTru22% (39)

    OpenAI 11 / Perplexity 8 / Claude 20

  4. 4APEC18% (33)

    OpenAI 10 / Perplexity 5 / Claude 18

  5. 5Brita18% (32)

    OpenAI 12 / Perplexity 5 / Claude 15

  6. 6iSpring17% (30)

    OpenAI 7 / Perplexity 7 / Claude 16

  7. 7ZeroWater14% (26)

    OpenAI 3 / Perplexity 4 / Claude 19

  8. 8SpringWell13% (23)

    OpenAI 3 / Perplexity 5 / Claude 15

  9. 9PUR12% (21)

    OpenAI 4 / Perplexity 2 / Claude 15

  10. 10LifeStraw11% (19)

    OpenAI 6 / Perplexity 3 / Claude 10

84 more brands named
  1. 11Berkey10% (18)

    OpenAI 0 / Perplexity 4 / Claude 14

    14 of these 18 from Claude

  2. 12Clearly Filtered8% (15)

    OpenAI 0 / Perplexity 1 / Claude 14

    14 of these 15 from Claude

  3. 13Brondell8% (14)

    OpenAI 2 / Perplexity 2 / Claude 10

  4. 13Culligan8% (14)

    OpenAI 5 / Perplexity 6 / Claude 3

  5. 13Weddell8% (14)

    OpenAI 4 / Perplexity 5 / Claude 5

  6. 16British Berkefeld6% (11)

    OpenAI 7 / Perplexity 2 / Claude 2

  7. 16Jolie6% (11)

    OpenAI 3 / Perplexity 2 / Claude 6

  8. 16Pentair6% (11)

    OpenAI 7 / Perplexity 1 / Claude 3

  9. 19Multipure6% (10)

    OpenAI 7 / Perplexity 1 / Claude 2

  10. 20Bluevua5% (9)

    OpenAI 2 / Perplexity 2 / Claude 5

  11. 20Frizzlife5% (9)

    OpenAI 1 / Perplexity 1 / Claude 7

    7 of these 9 from Claude

  12. 20Grayl5% (9)

    OpenAI 3 / Perplexity 3 / Claude 3

  13. 20Epic Water Filters5% (9)

    OpenAI 0 / Perplexity 1 / Claude 8

    8 of these 9 from Claude

  14. 20ProOne5% (9)

    OpenAI 0 / Perplexity 3 / Claude 6

  15. 20SoftPro5% (9)

    OpenAI 0 / Perplexity 0 / Claude 9

    All 9 from Claude

  16. 26Cloud RO4% (8)

    OpenAI 0 / Perplexity 1 / Claude 7

    7 of these 8 from Claude

  17. 26Express Water4% (8)

    OpenAI 3 / Perplexity 0 / Claude 5

  18. 26Home Master4% (8)

    OpenAI 0 / Perplexity 0 / Claude 8

    All 8 from Claude

  19. 26Kind4% (8)

    OpenAI 0 / Perplexity 0 / Claude 8

    All 8 from Claude

  20. 30A. O. Smith4% (7)

    OpenAI 2 / Perplexity 5 / Claude 0

  21. 30Aarke4% (7)

    OpenAI 3 / Perplexity 0 / Claude 4

  22. 30LARQ4% (7)

    OpenAI 2 / Perplexity 0 / Claude 5

  23. 333M3% (6)

    OpenAI 1 / Perplexity 5 / Claude 0

    5 of these 6 from Perplexity

  24. 34Fleck3% (5)

    OpenAI 1 / Perplexity 1 / Claude 3

  25. 34AquaBliss3% (5)

    OpenAI 0 / Perplexity 2 / Claude 3

  26. 34Boroux3% (5)

    OpenAI 0 / Perplexity 3 / Claude 2

  27. 34Whirlpool3% (5)

    OpenAI 2 / Perplexity 0 / Claude 3

  28. 34Canopy3% (5)

    OpenAI 0 / Perplexity 0 / Claude 5

    All 5 from Claude

  29. 34Santevia3% (5)

    OpenAI 0 / Perplexity 0 / Claude 5

    All 5 from Claude

  30. 40Clack2% (4)

    OpenAI 2 / Perplexity 2 / Claude 0

  31. 40Katadyn2% (4)

    OpenAI 1 / Perplexity 0 / Claude 3

  32. 40Kinetico2% (4)

    OpenAI 3 / Perplexity 1 / Claude 0

  33. 40Sprite2% (4)

    OpenAI 1 / Perplexity 0 / Claude 3

  34. 40Watts2% (4)

    OpenAI 3 / Perplexity 1 / Claude 0

  35. 40Hydroviv2% (4)

    OpenAI 0 / Perplexity 0 / Claude 4

  36. 46Amway eSpring2% (3)

    OpenAI 2 / Perplexity 1 / Claude 0

  37. 46Rheem2% (3)

    OpenAI 0 / Perplexity 2 / Claude 1

  38. 46Sonaki2% (3)

    OpenAI 2 / Perplexity 1 / Claude 0

  39. 46Afina2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  40. 46AquaCera2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  41. 46GE2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  42. 46NU Aqua2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  43. 46Patriot Pure2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  44. 46Phoenix2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  45. 46Second Shower2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  46. 46Viqua2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  47. 57Amazon Basics1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  48. 57Brio1% (2)

    OpenAI 2 / Perplexity 0 / Claude 0

  49. 57BWT1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  50. 57CuZn1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  51. 57EcoWater1% (2)

    OpenAI 0 / Perplexity 2 / Claude 0

  52. 57NuvoH2O1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  53. 57pH Replenish1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  54. 57Philips1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  55. 57RKIN1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  56. 57Rorra1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  57. 57SimPure1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  58. 57SodaStream1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  59. 57SpiroPure1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  60. 57Waterboss1% (2)

    OpenAI 0 / Perplexity 2 / Claude 0

  61. 71Alexapure<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  62. 71APEX<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  63. 71AquaYouth<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  64. 71CO-Z<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  65. 71Delta<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  66. 71DROP<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  67. 71Ecofiltro<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  68. 71EcoPure<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  69. 71Everpure<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  70. 71Filterbaby<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  71. 71Hello Klean<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  72. 71Kitsch<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  73. 71Moolmang<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  74. 71MOSAIC<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  75. 71Pelican<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  76. 71Platypus<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  77. 71Pure Water<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  78. 71Purewell<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  79. 71Soma<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  80. 71TDHKEI<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  81. 71UBS<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  82. 71VitaShower<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  83. 71WaterChef<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  84. 71weAqua<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

By engine

Each engine's answers counted on their own: the brands it named most, out of its own completed answers.

OpenAI (GPT via API, web search)

Model: gpt-6.1-sol. 60 of 60 answers completed.

  1. 1Aquasana
  2. 2Brita
  3. 3AquaTru
  4. 4APEC
  5. 5British Berkefeld
  6. 5iSpring
  7. 5Multipure
  8. 5Pentair
  9. 5Waterdrop

Perplexity (Agent API, web search)

Model: perplexity/sonar. 60 of 60 answers completed.

  1. 1Aquasana
  2. 2AquaTru
  3. 2Waterdrop
  4. 4iSpring
  5. 5Culligan

Claude (API, web search)

Model: claude-sonnet-5-5. 60 of 60 answers completed.

  1. 1Waterdrop
  2. 2Aquasana
  3. 3AquaTru
  4. 4ZeroWater
  5. 5APEC

Sites the answers cited

Each site is counted once per answer whose citation list included it, out of 180 answers, and grouped by domain.

  1. 1nsf.org36% (64)

    OpenAI 33 / Perplexity 30 / Claude 1

  2. 2epa.gov28% (51)

    OpenAI 27 / Perplexity 24 / Claude 0

  3. 3cdc.gov19% (34)

    OpenAI 27 / Perplexity 7 / Claude 0

  4. 4waterfilterguru.com17% (31)

    OpenAI 3 / Perplexity 0 / Claude 28

  5. 5aquasana.com13% (23)

    OpenAI 17 / Perplexity 6 / Claude 0

  6. 6worldwaterreserve.com12% (21)

    OpenAI 0 / Perplexity 1 / Claude 20

  7. 7tapwaterdata.com9% (17)

    OpenAI 0 / Perplexity 1 / Claude 16

  8. 8consumerreports.org9% (16)

    OpenAI 3 / Perplexity 7 / Claude 6

  9. 8qualitywaterlab.com9% (16)

    OpenAI 0 / Perplexity 1 / Claude 15

  10. 10techgearlab.com8% (14)

    OpenAI 0 / Perplexity 1 / Claude 13

184 more sites cited
  1. 11brita.com7% (13)

    OpenAI 12 / Perplexity 1 / Claude 0

  2. 11filtergearlab.com7% (13)

    OpenAI 0 / Perplexity 2 / Claude 11

  3. 13pentair.com6% (11)

    OpenAI 9 / Perplexity 1 / Claude 1

  4. 13waterverge.com6% (11)

    OpenAI 0 / Perplexity 1 / Claude 10

  5. 15aquatru.com6% (10)

    OpenAI 9 / Perplexity 1 / Claude 0

  6. 15filterpicks.com6% (10)

    OpenAI 0 / Perplexity 0 / Claude 10

  7. 17drinkingwaterfilter.com5% (9)

    OpenAI 0 / Perplexity 5 / Claude 4

  8. 17forbes.com5% (9)

    OpenAI 0 / Perplexity 4 / Claude 5

  9. 17apecwater.com5% (9)

    OpenAI 9 / Perplexity 0 / Claude 0

  10. 17nytimes.com5% (9)

    OpenAI 0 / Perplexity 9 / Claude 0

  11. 21cleanwatercritic.com4% (8)

    OpenAI 0 / Perplexity 5 / Claude 3

  12. 21cnn.com4% (8)

    OpenAI 0 / Perplexity 4 / Claude 4

  13. 21waterdropfilter.com4% (8)

    OpenAI 7 / Perplexity 1 / Claude 0

  14. 24culligan.com4% (7)

    OpenAI 6 / Perplexity 0 / Claude 1

  15. 24homedepot.com4% (7)

    OpenAI 4 / Perplexity 3 / Claude 0

  16. 24lifestraw.com4% (7)

    OpenAI 5 / Perplexity 2 / Claude 0

  17. 24amazon.com4% (7)

    OpenAI 0 / Perplexity 7 / Claude 0

  18. 24nbcnews.com4% (7)

    OpenAI 0 / Perplexity 0 / Claude 7

  19. 24waterfiltergeek.com4% (7)

    OpenAI 0 / Perplexity 0 / Claude 7

  20. 30springwellwater.com3% (6)

    OpenAI 3 / Perplexity 3 / Claude 0

  21. 30theexaminernews.com3% (6)

    OpenAI 0 / Perplexity 1 / Claude 5

  22. 30draxe.com3% (6)

    OpenAI 0 / Perplexity 0 / Claude 6

  23. 30emergencygearlab.com3% (6)

    OpenAI 0 / Perplexity 0 / Claude 6

  24. 30illyrianplumber.com3% (6)

    OpenAI 0 / Perplexity 0 / Claude 6

  25. 30nontoxiclab.com3% (6)

    OpenAI 0 / Perplexity 0 / Claude 6

  26. 30onegreenplanet.org3% (6)

    OpenAI 0 / Perplexity 0 / Claude 6

  27. 37grayl.com3% (5)

    OpenAI 3 / Perplexity 2 / Claude 0

  28. 37goodhousekeeping.com3% (5)

    OpenAI 0 / Perplexity 5 / Claude 0

  29. 37ispringfilter.com3% (5)

    OpenAI 5 / Perplexity 0 / Claude 0

  30. 37modernize.com3% (5)

    OpenAI 0 / Perplexity 5 / Claude 0

  31. 37thehomewaterlab.com3% (5)

    OpenAI 0 / Perplexity 5 / Claude 0

  32. 42interiormedicine.com2% (4)

    OpenAI 0 / Perplexity 1 / Claude 3

  33. 42lowes.com2% (4)

    OpenAI 2 / Perplexity 2 / Claude 0

  34. 42unl.edu2% (4)

    OpenAI 3 / Perplexity 1 / Claude 0

  35. 42wired.com2% (4)

    OpenAI 2 / Perplexity 2 / Claude 0

  36. 42bos-water.com2% (4)

    OpenAI 0 / Perplexity 0 / Claude 4

  37. 42doulton.com2% (4)

    OpenAI 4 / Perplexity 0 / Claude 0

  38. 42drinking-water.co2% (4)

    OpenAI 0 / Perplexity 0 / Claude 4

  39. 42plumbingpicks.com2% (4)

    OpenAI 0 / Perplexity 0 / Claude 4

  40. 42pur.com2% (4)

    OpenAI 4 / Perplexity 0 / Claude 0

  41. 42puritymap.com2% (4)

    OpenAI 0 / Perplexity 0 / Claude 4

  42. 42umn.edu2% (4)

    OpenAI 4 / Perplexity 0 / Claude 0

  43. 42weddellwater.com2% (4)

    OpenAI 4 / Perplexity 0 / Claude 0

  44. 54michigan.gov2% (3)

    OpenAI 1 / Perplexity 0 / Claude 2

  45. 54portland.gov2% (3)

    OpenAI 2 / Perplexity 1 / Claude 0

  46. 54psu.edu2% (3)

    OpenAI 2 / Perplexity 0 / Claude 1

  47. 54reddit.com2% (3)

    OpenAI 2 / Perplexity 1 / Claude 0

  48. 54state.mn.us2% (3)

    OpenAI 2 / Perplexity 1 / Claude 0

  49. 54aarke.us2% (3)

    OpenAI 3 / Perplexity 0 / Claude 0

  50. 54adaytrip.com2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  51. 54aquamarinepower.com2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  52. 54aquatruwater.com2% (3)

    OpenAI 3 / Perplexity 0 / Claude 0

  53. 54bobvila.com2% (3)

    OpenAI 0 / Perplexity 3 / Claude 0

  54. 54cleanwatermill.com2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  55. 54cleverhiker.com2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  56. 54cnet.com2% (3)

    OpenAI 0 / Perplexity 3 / Claude 0

  57. 54filteredtaphq.com2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  58. 54gearandhome.com2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  59. 54implasticfree.com2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  60. 54kinetico.com2% (3)

    OpenAI 3 / Perplexity 0 / Claude 0

  61. 54rei.com2% (3)

    OpenAI 0 / Perplexity 3 / Claude 0

  62. 54reverseosmosisguide.com2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  63. 54rkin.com2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  64. 54thatyurt.com2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  65. 54thebrokebackpacker.com2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  66. 54therunlow.com2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  67. 54thespruce.com2% (3)

    OpenAI 0 / Perplexity 3 / Claude 0

  68. 54thewell.guide2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  69. 54treelinereview.com2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  70. 54watersoftenerlab.com2% (3)

    OpenAI 0 / Perplexity 0 / Claude 3

  71. 54watts.com2% (3)

    OpenAI 3 / Perplexity 0 / Claude 0

  72. 54yahoo.com2% (3)

    OpenAI 0 / Perplexity 3 / Claude 0

  73. 83frizzlife.com1% (2)

    OpenAI 1 / Perplexity 0 / Claude 1

  74. 83thewaternerd.com1% (2)

    OpenAI 0 / Perplexity 1 / Claude 1

  75. 83allfilters.com1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  76. 83aosmithatlowes.com1% (2)

    OpenAI 2 / Perplexity 0 / Claude 0

  77. 83bonappetit.com1% (2)

    OpenAI 0 / Perplexity 2 / Claude 0

  78. 83britishwaterfilter.com1% (2)

    OpenAI 2 / Perplexity 0 / Claude 0

  79. 83brondell.com1% (2)

    OpenAI 2 / Perplexity 0 / Claude 0

  80. 83businesswire.com1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  81. 83checkmytap.com1% (2)

    OpenAI 0 / Perplexity 2 / Claude 0

  82. 83clackcorp.com1% (2)

    OpenAI 2 / Perplexity 0 / Claude 0

  83. 83completewaterguide.com1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  84. 83crystalquest.com1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  85. 83expresswater.com1% (2)

    OpenAI 2 / Perplexity 0 / Claude 0

  86. 83getplasticproof.com1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  87. 83goingzerowaste.com1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  88. 83hardwaterhq.com1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  89. 83ideal.house1% (2)

    OpenAI 0 / Perplexity 2 / Claude 0

  90. 83izreview.com1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  91. 83jolieskinco.com1% (2)

    OpenAI 2 / Perplexity 0 / Claude 0

  92. 83lacsd.org1% (2)

    OpenAI 2 / Perplexity 0 / Claude 0

  93. 83mawc.org1% (2)

    OpenAI 2 / Perplexity 0 / Claude 0

  94. 83midatlanticwater.net1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  95. 83mytapscore.com1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  96. 83pnnl.gov1% (2)

    OpenAI 2 / Perplexity 0 / Claude 0

  97. 83secondshower.us1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  98. 83sonaki.com1% (2)

    OpenAI 2 / Perplexity 0 / Claude 0

  99. 83tapwatersafety.org1% (2)

    OpenAI 0 / Perplexity 2 / Claude 0

  100. 83thekitchenprofessor.com1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  101. 83thisoldhouse.com1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  102. 83usda.gov1% (2)

    OpenAI 2 / Perplexity 0 / Claude 0

  103. 83wa.gov1% (2)

    OpenAI 2 / Perplexity 0 / Claude 0

  104. 83walmart.com1% (2)

    OpenAI 2 / Perplexity 0 / Claude 0

  105. 83watercheckup.com1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  106. 83waterfilter.guide1% (2)

    OpenAI 0 / Perplexity 2 / Claude 0

  107. 83whowhatwear.com1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  108. 83wikipedia.org1% (2)

    OpenAI 0 / Perplexity 0 / Claude 2

  109. 119advancestudy.org<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  110. 119aol.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  111. 119apple.com<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  112. 119aquabliss.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  113. 119barchart.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  114. 119bhg.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  115. 119bluevua.com<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  116. 119checkclearwater.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  117. 119cleanwaterstore.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  118. 119clearcarafe.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  119. 119clearwaterhomelab.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  120. 119countertopfilter.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  121. 119culligandiy.com<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  122. 119discountfilterstore.com<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  123. 119drinking-water.org<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  124. 119filterauthority.co.uk<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  125. 119filterbaby.com<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  126. 119foodnetwork.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  127. 119freshwatersystems.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  128. 119frontierplumbinglv.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  129. 119gadgetsfeed.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  130. 119h2oinsider.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  131. 119hardwatersolved.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  132. 119healthline.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  133. 119helloklean.com<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  134. 119homebrewfilters.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  135. 119homeessentialsguide.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  136. 119hometosight.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  137. 119icgi.org<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  138. 119katadyngroup.com<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  139. 119lucinn.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  140. 119madsewer.org<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  141. 119mindbodygreen.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  142. 119mnsplumbing.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  143. 119mrwatergeek.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  144. 119multipure.com<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  145. 119newworldsurvival.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  146. 119nontoxicfinder.com<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  147. 119outdoorgearlab.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  148. 119ownerspec.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  149. 119plumbingsupplyandmore.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  150. 119popsci.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  151. 119prooneusa.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  152. 119purcooflow.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  153. 119r3recs.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  154. 119sharehook.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  155. 119shopify.com<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  156. 119shouldit.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  157. 119slickdeals.net<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  158. 119sprucebath.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  159. 119state.pa.us<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  160. 119stormwatt.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  161. 119substack.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  162. 119target.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  163. 119teamblind.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  164. 119theconsumers.guide<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  165. 119thegoodforco.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  166. 119thehomepicker.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  167. 119thesafehealthyhome.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  168. 119thewaterhub.org<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  169. 119thewatermachine.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  170. 119thirstybear.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  171. 119vitashowercorp.com<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  172. 119vogue.co.uk<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  173. 119vt.edu<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  174. 119wal-mart.com<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  175. 119warmcazza.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  176. 119wateradvisor.org<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  177. 119waterchef.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  178. 119watersoftenersolutions.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  179. 119watersystemscouncil.org<1% (1)

    OpenAI 1 / Perplexity 0 / Claude 0

  180. 119wcponline.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  181. 119whatfilterremoves.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  182. 119witsengineer.com<1% (1)

    OpenAI 0 / Perplexity 0 / Claude 1

  183. 119wqa.org<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

  184. 119yourbestdigs.com<1% (1)

    OpenAI 0 / Perplexity 1 / Claude 0

The 20 questions

Asked word for word, 3 times on each engine.

  1. What's the best countertop water filter for tap water?
  2. What's the best whole-house water filter for well water?
  3. What's the best gravity water filter for home use?
  4. What's the best filtered water bottle for travel and hiking?
  5. My tap water tastes like chlorine. What filter should I buy?
  6. I want to filter PFAS out of my drinking water. Which filters are certified to do that?
  7. I have hard water. Should I buy a water softener or a salt-free conditioner, and which brands are good?
  8. I rent my apartment and can't install anything under the sink. What water filter should I buy?
  9. Reverse osmosis vs pitcher filter: which is better, and which brands are worth buying?
  10. Compare the most popular under-sink reverse osmosis brands.
  11. Whole-house filter vs under-sink filter: which do I need, and which brands are worth buying?
  12. Vitamin C vs KDF shower filters: which works better, and which brands should I look at?
  13. What's the best shower filter under $100?
  14. What's the best under-sink water filter under $200?
  15. Is it worth paying $500 or more for a countertop reverse osmosis system?
  16. What's the best whole-house water filter system under $1,000?
  17. What are good alternatives to buying bottled water for drinking at home?
  18. What are good alternatives to plastic water filter pitchers?
  19. What water filter brands do people recommend instead of the usual pitcher brands?
  20. What are good alternatives to a traditional salt-based water softener?

How we counted

OpenAI 60/60, Perplexity 60/60, Claude 60/60 completed answers, 20 buyer questions, 3 runs each, Nov 9, 2026

Asked
Nov 9, 2026
Engines and models
  • OpenAI (GPT via API, web search): gpt-6.1-sol
  • Perplexity (Agent API, web search): perplexity/sonar
  • Claude (API, web search): claude-sonnet-5-5
Completed answers
180 of 180
Named
An answer names a brand when it recommends it or lists it as an option to buy. A brand mentioned only to warn against it isn't counted, and a product counts for the brand that makes it.
Share of answers
The completed answers that named a brand, divided by all completed answers. Every answer counts the same, whichever engine gave it.

The answers counted here are AI output, and their factual claims can be wrong. Check them before relying on them.

Read the full method

Corrections

Think a count here is wrong? We check it against the stored answers and correct the page. Email hello@ecomindex.ai.

EcomIndex isn't affiliated with or endorsed by any brand, retailer or site named on this page. Brand, product and company names are trademarks of their owners.

Is your brand in this category?

The AI Shelf Report asks 20 questions written for your store and counts how often the answers name you and your competitors, with the sites they cite and a fix plan. $99, delivered within 2 business days.

Get your report: $99See a sample report