Email verification
Asked as “email verification service”, and as “email list validation tool”, on behalf of a mid-market B2B software company. 24 first choices recorded across the direct, paraphrase, budget and scale prompts, six models each.
Standing · first-choice share
33%
Contested · ZeroBounce 29%
33Bouncer29ZeroBounce08Kickbox29others
33% of first choices, contested.
The standing
Share is the count of first choices across the direct, paraphrase, budget and scale prompts, over all six models, for a mid-market B2B software company. Ordered by share.
ProductFirst-choice shareNegative rateLabelsQuadrantSince September 2026
Show the two products at 0%, ordered by negative rate
07
Hunter Email Verifier0%17%12accepted challengernewNew since September 2026: not ranked then, 0% now.
Hunter Email Verifier0%17%12accepted challengernewNew since September 2026: not ranked then, 0% now.The floor is 12 points of share, measured: how far the models move a leader on their own when the same questions are asked twice with nothing changed. A larger change is movement; a smaller one can't be told apart from repeat variation, and both are shown. Each index measures its own floor from its own repeat, over its own categories, so the floor differs from one index to the next. How the floor is measured
Bars are the share of first choices, 0 to 100Every product with at least 10 labels here. Every product name links to its product page.
All ten head-to-head pages: the top five products, each against each
Recommended versus criticized
Every product with at least 10 labels here, on both axes. The 30% line names a quadrant, not the verdict above: that one needs more than 40%.
Criticized challengerCriticized default
Negative label rate →
01
02
03
04
05
0607Accepted challengerEndorsed leader
0%First-choice share → · lines at 30% share and 25% negative50%
Key
01Bouncer33%
Bouncer33%02ZeroBounce29%
ZeroBounce29%03NeverBounce8%
NeverBounce8%04Kickbox8%
Kickbox8%05MillionVerifier8%
MillionVerifier8%06Emailable0%
Emailable0%07Hunter Email Verifier0%
Hunter Email Verifier0%What they warned about
Two of six models held their first choice under the paraphrase. Claude Opus 5, Claude Opus 4.8, Gemini 3.1 Pro and Perplexity Sonar Pro changed. A high negative share on a product with few labels is a warning. A low share on a product with many labels is salience, not sentiment.
ZeroBounce17%
5 of 29 labels negative · 5 of 6 models
“That warrants caution about generalizing its rankings—not a conclusion that ZeroBounce or its competitors are untrustworthy.” GPT-6 Astra, negative prompt
Verifications.io
100%
3 of 3 labels negative · 3 of 6 models · 3 hard negative
“Verifications.io—or any service claiming to be its continuation. The original company is defunct following a 2019 exposure” GPT-5.6 Sol, negative prompt
NeverBounce14%
3 of 22 labels negative · 3 of 6 models
“only around 8/16 in that disposable-email test, so I’d treat them as tools to test carefully on your own list” Perplexity Sonar Pro, negative prompt
MillionVerifier23%
3 of 13 labels negative · 2 of 6 models · 1 hard negative
“ranked it near the bottom at 4/16, and another review flagged concerns about higher bounce rates and slower API response times” Perplexity Sonar Pro, negative prompt
What they cite
Six of the six models returned a source list in this edition: six return the pages they cited.
Sites the answers cite
31 of 36 answers in this category came back with a source list, from 6 of 6 models: citations where the model returns them, or the search results it consulted. 536 links across 160 sites, every framing counted. Ranked by the number of answers carrying the site or page. None of the 36 answers across every segment cited this index's own page for the category.
26 answers · 51 citations · 6 models
vendor site · ZeroBounce22 answers · 39 citations · 5 models
vendor site · Hunter16 answers · 22 citations · 6 models
16 answers · 17 citations · 3 models
vendor site · BillionVerify12 answers · 14 citations · 4 models
vendor site · Mailtrap11 answers · 11 citations · 3 models
9 answers · 14 citations · 3 models
vendor site · Sparkle.io9 answers · 10 citations · 3 models
vendor site · Instantly9 answers · 9 citations · 2 models
vendor site · Snov.io9 answers · 9 citations · 4 models
7 answers · 14 citations · 3 models
vendor site · MyEmailVerifier7 answers · 11 citations · 3 models
Pages the answers cite
The ten pages named in the most answers, by full address. A page here is one the models returned with a recommendation, not one the index endorses.
16 answers · 3 models
13 answers · 4 models
11 answers · 3 models
8 answers · 4 models
7 answers · 2 models
6 answers · 3 models
6 answers · 3 models
6 answers · 2 models
6 answers · 3 models
6 answers · 3 models
Search against answers
Each company's standing in the answers beside its site's footprint in Google search, one row a site: the products the models named on it with their shares, and the share they add up to; monthly searches on Google, and DataForSEO's estimate of AI search demand (modeled from search signals, directional, not a count of queries to any assistant), for the most-searched of the company's and its products' names (the name is in each row's hover text); estimated monthly organic visits to the site; and its best position in Google's top ten for “best email verification service”, “email verification service”. US estimates from DataForSEO and Google's Ads Transparency Center. A small company's site, or a mid-sized company's site for its flagship, is marked company; a product on a large parent's site (Google, Microsoft) has no site figures. A column with no figures for this category is left out, and an empty cell means none were seen, not none exist. Two measurements side by side: neither is read as the cause of the other.
| Company and products | Share | Own site cited | Name searches, Google | AI search demand, est. | Organic visits | Paid search a month, est. | Google ads, last 30 days | Best Google position |
|---|---|---|---|---|---|---|---|---|
| Bouncer usebouncer.com | 33% | 124 | 27,100 | 6,621 | 9,553 | 24 | 6 | |
| ZeroBounce zerobounce.net | 29% | 250 | 9,900 | 118 | 38,183 | $778 | 120 | 2 |
| NeverBounce neverbounce.com | 8% | 155 | 8,100 | 64 | 73,301 | 16 | ||
| Kickbox kickbox.com | 8% | 140 | 74,000 | 15,514 | 39,936 | 31 | ||
| MillionVerifier millionverifier.com | 8% | 51 | 1,900 | 1 | 1,260 | 4 | ||
| EmailListVerify emaillistverify.com | 4% | 36 | 480 | 1 | 11,192 | 24 | ||
| DeBounce debounce.com | 4% | 42 | 3,600 | 661 | 4,116 | |||
| MyEmailVerifier myemailverifier.com | 4% | 23 | 170 | 0 | 3,222 | 5 | ||
| Emailable emailable.com | 0% | 75 | 880 | 601,367 | 10,645 | 0 | 6 | |
| Hunter Email Verifier hunter.io | 0% | 46 | 5,400 | 0 | 152,782 | 6 | 5 |
Google's top ten for the two searches hold 16 sites; 5 of them are among the sites the models cited here (emailvendorselection.com, hunter.io, mailtrap.io, usebouncer.com, zerobounce.net). The first result for “best email verification service” is reddit.com.
How they answered
Six framings of the same buying question, each sent to every model in a fresh session with search on. One row per model, so a row shows whether it held its answer under rewording, what it named when cost was the constraint, and what it argued against. Computed from the raw judge labels.ShowHide
How they answered
Six framings of the same buying question, each sent to every model in a fresh session with search on. One row per model, so a row shows whether it held its answer under rewording, what it named when cost was the constraint, and what it argued against. Computed from the raw judge labels.
ShowHideModelDirect“What is the best email verification service for a mid-market B2B software company?”Paraphrase“Which email list validation tool would you recommend to a mid-sized B2B software company?”Comparative“What are the top email verification services and how do they differ?”Budget-constrained“What is the best email verification service for a company with a limited budget?”Scale-constrained“We are a 500 person company evaluating an email verification service. What should we look at?”Negative“Which email verification services should I avoid or be cautious about?”
Claude Opus 5Bounceragainst: KickboxKickbox, ZeroBounceChangedBouncer, ZeroBounceagainst: NeverBounceMillionVerifierno first choiceagainst: BulkEmailVerification, Kickbox, MyEmailVerifier, QuickEmailVerifier, ZeroBounceagainst: MillionVerifier, Verifications.io
Two alternatives
NeverBounce, ZeroBounceFive alternatives
BounceBan, Bouncer, Findymail, LeadMagic, MillionVerifierSix alternatives
Clearout, DeBounce, Emailable, Hunter Email Verifier, Kickbox, MillionVerifierFive alternatives
Bouncer, EmailListVerify, Hunter Email Verifier, MyEmailVerifier, ZeroBounceClaude Opus 4.8Kickbox, ZeroBounceNeverBounce, ZeroBounceChangedZeroBounceBouncer, MyEmailVerifieragainst: ZeroBounceno first choicenothing named
Two alternatives
Bouncer, NeverBounceThree alternatives
Bouncer, Kickbox, MillionVerifierThree alternatives
Bouncer, Hunter Email Verifier, NeverBounceTwo alternatives
Clearout, NeverBounceGPT-6 AstraZeroBounceZeroBounceHeldBouncerBouncer, MillionVerifierno first choiceagainst: Verifications.io, ZeroBounce
One alternative
BouncerFive alternatives
Clearout, Hunter Email Verifier, MillionVerifier, NeverBounce, ZeroBounceOne alternative
ZeroBounceGPT-5.6 SolBouncerBouncerHeldBouncer, ZeroBounceBounceragainst: ZeroBounceno first choiceagainst: Bouncer, Hunter Email Verifier, Verifications.io, VerifiedEmail
Two alternatives
Emailable, ZeroBounceOne alternative
ZeroBounceSix alternatives
BriteVerify, Emailable, Hunter Email Verifier, Kickbox, MailerSend, NeverBounceTwo alternatives
MailTester, Reoon Email VerifierGemini 3.1 ProNeverBounceZeroBounceChangedClearout, ZeroBounceDeBounceagainst: NeverBounce, ZeroBounceno first choiceagainst: Apollo.io, Email List Validation, Hunter Email Verifier, Mailgun, Mails.so, Snov.io
Three alternatives
Bouncer, Kickbox, ZeroBounceThree alternatives
Bouncer, Hunter Email Verifier, NeverBounceFive alternatives
Bouncer, Emailable, Hunter Email Verifier, Kickbox, NeverBounceFour alternatives
BillionVerify, Bouncer, EmailListVerify, MillionVerifierPerplexity Sonar ProBouncer, ZeroBounceBouncerChangedno first choiceEmailListVerifyagainst: MillionVerifierno first choiceagainst: BounceBan, MillionVerifier, NeverBounce, QuickEmailVerification, WhoisXML
One alternative
NeverBounceThree alternatives
Hunter Email Verifier, NeverBounce, ZeroBounceOne alternative
BouncerBold is the first choiceAlternatives are counted; the count opens them.What the answer argued against
The record
One row per call: the version string exactly as returned, whether the model searched, sources cited, and latency.
Thirty-six rows: every prompt, every model, every answer.
| Prompt | Model | Version string | Time (UTC) | Searched | Sources | Latency |
|---|---|---|---|---|---|---|
| Direct recommendation | Claude Opus 5 | claude-opus-5 | 2026-09-09 20:29 | yes | 26 | 61 s |
| Direct recommendation | Claude Opus 4.8 | claude-opus-4-8 | 2026-09-09 20:31 | yes | 39 | 51 s |
| Direct recommendation | GPT-6 Astra | gpt-6-astra | 2026-09-09 20:33 | yes | 5 | 36 s |
| Direct recommendation | GPT-5.6 Sol | gpt-5.6-sol | 2026-09-09 20:35 | yes | 5 | 39 s |
| Direct recommendation | Gemini 3.1 Pro | gemini-3.1-pro-preview | 2026-09-10 18:45 | no | 0 | 22 s |
| Direct recommendation | Perplexity Sonar Pro | sonar-pro | 2026-09-09 20:31 | yes | 20 | 4 s |
| Paraphrase | Claude Opus 5 | claude-opus-5 | 2026-09-09 20:37 | yes | 23 | 69 s |
| Paraphrase | Claude Opus 4.8 | claude-opus-4-8 | 2026-09-09 20:38 | no | 0 | 21 s |
| Paraphrase | GPT-6 Astra | gpt-6-astra | 2026-09-09 20:40 | yes | 6 | 27 s |
| Paraphrase | GPT-5.6 Sol | gpt-5.6-sol | 2026-09-09 20:41 | yes | 5 | 37 s |
| Paraphrase | Gemini 3.1 Pro | gemini-3.1-pro-preview | 2026-09-10 18:46 | yes | 5 | 35 s |
| Paraphrase | Perplexity Sonar Pro | sonar-pro | 2026-09-09 20:39 | yes | 20 | 3 s |
| Comparative | Claude Opus 5 | claude-opus-5 | 2026-09-09 20:45 | yes | 27 | 147 s |
| Comparative | Claude Opus 4.8 | claude-opus-4-8 | 2026-09-09 20:47 | yes | 30 | 64 s |
| Comparative | GPT-6 Astra | gpt-6-astra | 2026-09-09 20:50 | yes | 9 | 46 s |
| Comparative | GPT-5.6 Sol | gpt-5.6-sol | 2026-09-09 20:52 | yes | 10 | 62 s |
| Comparative | Gemini 3.1 Pro | gemini-3.1-pro-preview | 2026-09-10 18:47 | yes | 10 | 38 s |
| Comparative | Perplexity Sonar Pro | sonar-pro | 2026-09-10 19:13 | yes | 20 | 7 s |
| Budget constrained | Claude Opus 5 | claude-opus-5 | 2026-09-09 20:54 | yes | 36 | 45 s |
| Budget constrained | Claude Opus 4.8 | claude-opus-4-8 | 2026-09-09 20:56 | yes | 33 | 48 s |
| Budget constrained | GPT-6 Astra | gpt-6-astra | 2026-09-09 20:57 | yes | 3 | 22 s |
| Budget constrained | GPT-5.6 Sol | gpt-5.6-sol | 2026-09-09 20:58 | yes | 4 | 18 s |
| Budget constrained | Gemini 3.1 Pro | gemini-3.1-pro-preview | 2026-09-10 18:49 | yes | 21 | 33 s |
| Budget constrained | Perplexity Sonar Pro | sonar-pro | 2026-09-09 20:56 | yes | 20 | 6 s |
| Scale constrained | Claude Opus 5 | claude-opus-5 | 2026-09-09 21:00 | yes | 26 | 47 s |
| Scale constrained | Claude Opus 4.8 | claude-opus-4-8 | 2026-09-09 21:01 | no | 0 | 20 s |
| Scale constrained | GPT-6 Astra | gpt-6-astra | 2026-09-09 21:02 | yes | 6 | 33 s |
| Scale constrained | GPT-5.6 Sol | gpt-5.6-sol | 2026-09-09 21:04 | yes | 5 | 49 s |
| Scale constrained | Gemini 3.1 Pro | gemini-3.1-pro-preview | 2026-09-10 18:50 | no | 0 | 24 s |
| Scale constrained | Perplexity Sonar Pro | sonar-pro | 2026-09-09 21:01 | yes | 20 | 13 s |
| Negative framing | Claude Opus 5 | claude-opus-5 | 2026-09-09 21:06 | yes | 37 | 65 s |
| Negative framing | Claude Opus 4.8 | claude-opus-4-8 | 2026-09-09 21:13 | yes | 33 | 140 s |
| Negative framing | GPT-6 Astra | gpt-6-astra | 2026-09-09 21:15 | yes | 6 | 35 s |
| Negative framing | GPT-5.6 Sol | gpt-5.6-sol | 2026-09-09 21:17 | yes | 6 | 42 s |
| Negative framing | Gemini 3.1 Pro | gemini-3.1-pro-preview | 2026-09-10 18:51 | no | 0 | 36 s |
| Negative framing | Perplexity Sonar Pro | sonar-pro | 2026-09-09 21:13 | yes | 20 | 4 s |
Normalization in this category
Every judgment call made between the raw labels and the numbers above, listed so it is visible and reversible.
ShowHide
Category-scoped readings
Hunter read as Hunter Email Verifier
Hunter (Hunter.io) read as Hunter Email Verifier
Hunter.io read as Hunter Email Verifier
Reoon read as Reoon Email Verifier
Unresolved, counted raw
None awaiting human review.
Discontinued, still offered
No shut-down product was recommended here.