GTM AI Index
September 2026 Edition · The permanent record of this edition. The unqualified address always carries the latest edition.
Index › GTM data and infrastructure › Email verification › Enterprise › September 2026 Edition

Email verification for enterprise buyers

Asked as “email verification service”, and as “email list validation tool”, on behalf of an enterprise B2B company. 47 first choices recorded across the direct, paraphrase, budget and scale prompts, twelve models each.
Standing
ZeroBounce
Clear leader
51% of first choices, clear leader.
ShowinginAll 73 categories in the September 2026 Edition →

By buyer segment

The same question asked on behalf of a different buyer. Each standing is computed within its segment; they sit side by side and are never added together.
Small businessBouncer33%ContestedStanding →Mid-marketZeroBounce29%ContestedStanding →EnterpriseZeroBounce51%Clear leaderThis page

01The standing

Share is the count of first choices across the direct, paraphrase, budget and scale prompts, over all twelve models, for an enterprise B2B company. Ordered by share.
ProductFirst-choice shareNegative rateLabelsQuadrant
01ZeroBounce51%0%57endorsed leader
02NeverBounce6%9%44accepted challenger
03Hunter6%24%21accepted challenger
04ZoomInfo6%0%10accepted challenger
05Kickbox4%3%32accepted challenger
06Bouncer4%9%33accepted challenger
Show the three products at 0%, ordered by negative rate
09BriteVerify0%30%10criticized challenger
08Clearout0%7%15accepted challenger
07Emailable0%5%20accepted challenger
Bars are the share of first choices, 0 to 100Every product with at least 10 labels here. Every product name links to its vendor page.
Head to head
ZeroBounce vs BouncerZeroBounce vs HunterBouncer vs Hunter

One product takes 51% of first choices here, so the chart would put eight markers in one corner and one at the far edge. The two measurements it plots are columns in the standing above: share, and the negative label rate. One product carries a negative rate above 25% in this category. Jump to the standing

02What they warned about

Seven of twelve models held their first choice under the paraphrase. Claude Haiku 4.5, DeepSeek V4 Flash, Llama 4 Maverick, GLM 4.7 FlashX and MiniMax M2.5 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.
Verifications.io
100%
5 of 5 labels negative · 5 of 12 models · 5 hard negative
“Avoid: Services with Severe Historical Red Flags ... Why avoid: In 2019, this service suffered one of the largest data breaches in history” DeepSeek V4 Flash, negative prompt
MillionVerifier
75%
6 of 8 labels negative · 4 of 12 models · 3 hard negative
“describe the company as a "shell company" with no real customer support ... this level of unreliability and non-responsiveness is unacceptable” DeepSeek V4 Flash, negative prompt
DeBounce
50%
4 of 8 labels negative · 4 of 12 models · 1 hard negative
“Popular budget services (such as *DeBounce*) are widely used for small projects but lack these critical certifications.” Gemini 3.5 Flash, negative prompt
Hunter
24%
5 of 21 labels negative · 4 of 12 models
“its per-email cost is significantly higher than dedicated verifiers ... too expensive for pure verification” Qwen 3.7 Flash, negative prompt

03What they cite

Citations exist only for the models that return a source list: four of the twelve in this edition, and all six flagship models on the expanded tier.

Sites the answers cite

23 of 72 answers in this category came back with a source list, from 4 of 12 models: citations where the model returns them, or the search results it consulted. 6 of those lists are Google grounding redirects that name no site and are left out of the counts. 215 links across 99 sites, every framing counted. Ranked by the number of answers carrying the site or page. The other 8 models searched through a gateway that returned no source list on this edition.

zerobounce.net
vendor site · ZeroBounce11 answers · 18 citations · 2 models
hunter.io
vendor site · Hunter9 answers · 10 citations · 2 models
usebouncer.com
8 answers · 17 citations · 3 models
pipeline.zoominfo.com
vendor site · ZoomInfo6 answers · 10 citations · 2 models
overloop.com
vendor site · Overloop6 answers · 6 citations · 1 model
lagrowthmachine.com
vendor site · La Growth Machine5 answers · 6 citations · 2 models
clearout.io
vendor site · Clearout5 answers · 5 citations · 1 model
cleanlist.ai
vendor site · Cleanlist4 answers · 4 citations · 1 model
learn.g2.com
4 answers · 4 citations · 2 models
mailtrap.io
vendor site · Mailtrap4 answers · 4 citations · 2 models
snov.io
vendor site · Snov.io4 answers · 4 citations · 2 models
g2.com
3 answers · 4 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.

hunter.io/email-verification-guide/best-email-verifiers
8 answers · 2 models
overloop.com/blog/email-verification-guide
6 answers · 1 model
pipeline.zoominfo.com/marketing/email-verification-tools
5 answers · 2 models
zerobounce.net/
5 answers · 1 model
clearout.io/email-verification-tools
4 answers · 1 model
learn.g2.com/best-email-verification-software
4 answers · 2 models
mailtrap.io/blog/email-verification-tools
4 answers · 2 models
pipeline.zoominfo.com/operations/email-finder-verification-tools
4 answers · 2 models
usebouncer.com/best-email-verification-tools
4 answers · 2 models
usebouncer.com/email-list-verification-service
4 answers · 1 model

04How 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.
ModelDirect“What is the best email verification service for an enterprise B2B company?”Paraphrase“Which email list validation tool would you recommend to a large B2B company with thousands of employees?”Comparative“What are the top enterprise-grade email verification services and how do they differ?”Budget-constrained“What is the best email verification service for a large company that needs predictable total cost across thousands of users?”Scale-constrained“We are a 5,000 person company with SSO, SOC 2 and procurement review requirements evaluating an email verification service. What should we look at?”Negative“Which email verification services should a large enterprise avoid or be cautious about?”
Claude Haiku 4.5Skrapp
Three alternativesAllegrow, ZeroBounce, ZoomInfo
NeverBounce, ZeroBounceChanged
One alternativeMillionVerifier
no first choiceTruelist, Unlimited Verifierno first choicenothing named
GPT-5.4 miniZeroBounce
Two alternativesBouncer, Emailable
ZeroBounceHeld
One alternativeMailgun Validate
ZeroBounce
Three alternativesBouncer, BriteVerify / Validity Verify, Hunter
ZeroBounceno first choiceagainst: Kickbox, MailTester, Xverify
Gemini 3.5 FlashZeroBounce
Three alternativesBouncer, BriteVerify, NeverBounce
ZeroBounceHeld
Two alternativesBouncer, NeverBounce
ZeroBounce
Five alternativesBouncer, BriteVerify, Emailable, Kickbox, NeverBounce
Bulk Email Checker, ZeroBounce
Three alternativesBouncer, Plauti Verify, Truelist
Kickbox
Two alternativesBriteVerify, ZeroBounce
against: DeBounce, Verifications.io
Perplexity SonarZeroBounce
Three alternativesBouncer, NeverBounce, ZoomInfo
ZeroBounceHeld
Two alternativesBouncer, ZoomInfo
ZeroBounce
Six alternativesBouncer, Clearout, Emailable, Hunter, Kickbox, NeverBounce
ZeroBounce
One alternativeEmailListVerify
against: Bouncerno first choiceagainst: DeBounce, Email List Verify, Emailable, Enrichley, Findymail, Lead Magic, MailerCheck, NeverBounce
Grok 4.1 FastZeroBounce
Five alternativesBouncer, Clearout, Hunter, Kickbox, NeverBounce
ZeroBounceHeld
Two alternativesKickbox, NeverBounce
against: HunterZeroBounce
Three alternativesBouncer, Kickbox, NeverBounce
against: BriteVerify, HunterZeroBounce
Three alternativesBulkEmailChecker, Kickbox, Truelist
against: Bouncer, NeverBounceZeroBounce
Two alternativesBouncer, Emailable
against: Clearout, DeBounce, Email List Validation, EmailListVerify, MillionVerifier, Verifications.io
Mistral SmallZoomInfo
Four alternativesAllegrow, Cognism, Kickbox, ZeroBounce
ZoomInfoHeld
Two alternativesNeverBounce, ZeroBounce
Bouncer, ZeroBounce
Five alternativesClearout, Emailable, Hunter, MillionVerifier, NeverBounce
BillionVerify
Two alternativesEmailListValidation, ZeroBounce
no first choicenothing named
DeepSeek V4 FlashHunter, ZeroBounce
Three alternativesClearout, Kickbox, NeverBounce
KickboxChanged
Two alternativesNeverBounce, ZeroBounce
NeverBounce, ZeroBounce
Three alternativesBouncer, Emailable, Kickbox
against: Hunter, MillionVerifierBulkEmailChecker's Unlimited API
Two alternativesNeverBounce, ZeroBounce
ZeroBounce
One alternativeKickbox
against: DeBounce, MillionVerifier, NeverBounceagainst: MillionVerifier, NeverBounce, Snov.io, Verifications.io
Llama 4 MaverickNeverBounce
Two alternativesZeroBounce, ZoomInfo
ZeroBounceChanged
Three alternativesBouncer, Cleanlist, Hunter
no first choiceZeroBounce
Two alternativesDeBounce, NeverBounce
no first choicenothing named
Qwen 3.7 FlashZeroBounce
Seven alternativesBriteVerify, Emailable, Hunter, Kickbox, NeverBounce, Prospeo, Puzzly
ZeroBounceHeld
Three alternativesKickbox, NeverBounce, Verifalia
ZeroBounce
Five alternativesBouncer, Clearout, Emailable, Kickbox, NeverBounce
Unlimited Verifier
Four alternativesBulkEmailChecker, Clearout, NeverBounce, ZeroBounce
no first choiceagainst: Apollo.io, Enrichley, Findymail, Hunter, Lead Magic, MailerCheck, Snov.io
Kimi K2ZeroBounce
Two alternativesKickbox, NeverBounce
ZeroBounceHeld
Two alternativesBouncer, Kickbox
ZeroBounce
Five alternativesBouncer, Clearout, Emailable, Kickbox, NeverBounce
against: BriteVerifyBulk Email Checker, Hunter
Two alternativesKickbox, NeverBounce
against: Apollo.iono first choice
Four alternativesBriteVerify, Kickbox, NeverBounce, ZeroBounce
against: Bounceragainst: EmailListVerify, HubSpot, Mailchimp, MillionVerifier, Verifications.io
GLM 4.7 FlashXZeroBounce
Three alternativesBouncer, Kickbox, NeverBounce
against: HunterBouncerChanged
Four alternativesEmailable, Kickbox, NeverBounce, ZeroBounce
NeverBounce
Six alternativesBouncer, Clearout, Emailable, Hunter, Kickbox, ZeroBounce
Bouncer
Two alternativesNeverBounce, ZeroBounce
against: MillionVerifierno first choiceagainst: Verifications.io
MiniMax M2.5NeverBounce, ZeroBounce, ZoomInfo
One alternativeBouncer
Cleanlist, HunterChanged
Two alternativesClearout, ZoomInfo
NeverBounce
Four alternativesClearout, Emailable, Kickbox, ZeroBounce
against: BriteVerifyBulkEmailChecker Unlimited API
Three alternativesMailValid, NeverBounce, ZeroBounce
no first choicenothing named
Bold is the first choiceAlternatives are counted; the count opens them.What the answer argued against

05The record

One row per call: the version string exactly as returned, whether the model searched, sources cited, and latency. Full answer text is in the free responses file. Download the record
Seventy-two rows: every prompt, every model, every answer.
PromptModelVersion stringTime (UTC)SearchedSourcesLatency
Direct recommendationClaude Haiku 4.5claude-haiku-4-5-202510012026-09-15 02:19yes68 s
Direct recommendationGPT-5.4 minigpt-5.4-mini-2026-03-172026-09-14 23:20yes45 s
Direct recommendationGemini 3.5 Flashgemini-3.5-flash2026-09-15 01:32yes2426 s
Direct recommendationPerplexity Sonarsonar2026-09-15 03:40yes206 s
Direct recommendationGrok 4.1 Fastspacexai/grok-4.1-fast-non-reasoning via vertex2026-09-15 03:47yes011 s
Direct recommendationMistral Smallmistral/mistral-small via mistral2026-09-15 00:47yes08 s
Direct recommendationDeepSeek V4 Flashdeepseek/deepseek-v4-flash via fireworks2026-09-15 02:29yes015 s
Direct recommendationLlama 4 Maverickmeta/llama-4-maverick via bedrock2026-09-15 00:34yes01 s
Direct recommendationQwen 3.7 Flashalibaba/qwen3.7-flash via alibaba2026-09-15 04:16yes031 s
Direct recommendationKimi K2moonshotai/kimi-k2 via novita2026-09-15 03:28yes033 s
Direct recommendationGLM 4.7 FlashXzai/glm-4.7-flashx via zai2026-09-14 23:33yes034 s
Direct recommendationMiniMax M2.5minimax/minimax-m2.5 via minimax2026-09-14 23:38yes020 s
ParaphraseClaude Haiku 4.5claude-haiku-4-5-202510012026-09-14 22:53yes88 s
ParaphraseGPT-5.4 minigpt-5.4-mini-2026-03-172026-09-15 05:03yes27 s
ParaphraseGemini 3.5 Flashgemini-3.5-flash2026-09-14 23:17yes1019 s
ParaphrasePerplexity Sonarsonar2026-09-15 00:38yes205 s
ParaphraseGrok 4.1 Fastspacexai/grok-4.1-fast-non-reasoning via vertex2026-09-15 01:54yes09 s
ParaphraseMistral Smallmistral/mistral-small via mistral2026-09-15 00:58yes08 s
ParaphraseDeepSeek V4 Flashdeepseek/deepseek-v4-flash via deepinfra2026-09-14 23:10yes036 s
ParaphraseLlama 4 Maverickmeta/llama-4-maverick via bedrock2026-09-15 02:55yes02 s
ParaphraseQwen 3.7 Flashalibaba/qwen3.7-flash via alibaba2026-09-15 01:39no039 s
ParaphraseKimi K2moonshotai/kimi-k2 via novita2026-09-14 23:23yes033 s
ParaphraseGLM 4.7 FlashXzai/glm-4.7-flashx via zai2026-09-15 00:04yes034 s
ParaphraseMiniMax M2.5minimax/minimax-m2.5 via minimax2026-09-15 01:57yes014 s
ComparativeClaude Haiku 4.5claude-haiku-4-5-202510012026-09-15 01:30yes69 s
ComparativeGPT-5.4 minigpt-5.4-mini-2026-03-172026-09-14 23:56yes914 s
ComparativeGemini 3.5 Flashgemini-3.5-flash2026-09-15 04:14yes2928 s
ComparativePerplexity Sonarsonar2026-09-15 01:12yes2011 s
ComparativeGrok 4.1 Fastspacexai/grok-4.1-fast-non-reasoning via vertex2026-09-15 03:21yes08 s
ComparativeMistral Smallmistral/mistral-small via mistral2026-09-15 01:47yes09 s
ComparativeDeepSeek V4 Flashdeepseek/deepseek-v4-flash via fireworks2026-09-15 00:47yes032 s
ComparativeLlama 4 Maverickmeta/llama-4-maverick via bedrock2026-09-15 00:15yes01 s
ComparativeQwen 3.7 Flashalibaba/qwen3.7-flash via alibaba2026-09-15 04:33yes036 s
ComparativeKimi K2moonshotai/kimi-k2 via novita2026-09-15 01:16yes096 s
ComparativeGLM 4.7 FlashXzai/glm-4.7-flashx via zai2026-09-15 01:37yes066 s
ComparativeMiniMax M2.5minimax/minimax-m2.5 via minimax2026-09-15 01:36yes011 s
Budget constrainedClaude Haiku 4.5claude-haiku-4-5-202510012026-09-15 03:32yes158 s
Budget constrainedGPT-5.4 minigpt-5.4-mini-2026-03-172026-09-15 04:19yes29 s
Budget constrainedGemini 3.5 Flashgemini-3.5-flash2026-09-15 00:18yes1929 s
Budget constrainedPerplexity Sonarsonar2026-09-15 04:35yes205 s
Budget constrainedGrok 4.1 Fastspacexai/grok-4.1-fast-non-reasoning via vertex2026-09-15 04:36yes018 s
Budget constrainedMistral Smallmistral/mistral-small via mistral2026-09-15 03:23yes07 s
Budget constrainedDeepSeek V4 Flashdeepseek/deepseek-v4-flash via deepinfra2026-09-15 04:48yes028 s
Budget constrainedLlama 4 Maverickmeta/llama-4-maverick via bedrock2026-09-14 23:37yes02 s
Budget constrainedQwen 3.7 Flashalibaba/qwen3.7-flash via alibaba2026-09-15 01:58yes033 s
Budget constrainedKimi K2moonshotai/kimi-k2 via novita2026-09-15 04:23yes039 s
Budget constrainedGLM 4.7 FlashXzai/glm-4.7-flashx via zai2026-09-15 00:45yes017 s
Budget constrainedMiniMax M2.5minimax/minimax-m2.5 via minimax2026-09-15 00:40yes035 s
Scale constrainedClaude Haiku 4.5claude-haiku-4-5-202510012026-09-15 01:09yes1511 s
Scale constrainedGPT-5.4 minigpt-5.4-mini-2026-03-172026-09-15 00:14no09 s
Scale constrainedGemini 3.5 Flashgemini-3.5-flash2026-09-14 23:59yes1730 s
Scale constrainedPerplexity Sonarsonar2026-09-15 00:32yes2012 s
Scale constrainedGrok 4.1 Fastspacexai/grok-4.1-fast-non-reasoning via vertex2026-09-15 03:27yes07 s
Scale constrainedMistral Smallmistral/mistral-small via mistral2026-09-15 03:40no09 s
Scale constrainedDeepSeek V4 Flashdeepseek/deepseek-v4-flash via deepinfra2026-09-14 22:59yes087 s
Scale constrainedLlama 4 Maverickmeta/llama-4-maverick via bedrock2026-09-15 01:04yes03 s
Scale constrainedQwen 3.7 Flashalibaba/qwen3.7-flash via alibaba2026-09-14 23:46no028 s
Scale constrainedKimi K2moonshotai/kimi-k2 via novita2026-09-15 03:20yes046 s
Scale constrainedGLM 4.7 FlashXzai/glm-4.7-flashx via zai2026-09-15 03:46yes088 s
Scale constrainedMiniMax M2.5minimax/minimax-m2.5 via minimax2026-09-15 02:22yes016 s
Negative framingClaude Haiku 4.5claude-haiku-4-5-202510012026-09-15 02:05yes2411 s
Negative framingGPT-5.4 minigpt-5.4-mini-2026-03-172026-09-15 04:08yes411 s
Negative framingGemini 3.5 Flashgemini-3.5-flash2026-09-14 22:52yes1926 s
Negative framingPerplexity Sonarsonar2026-09-14 23:40yes206 s
Negative framingGrok 4.1 Fastspacexai/grok-4.1-fast-non-reasoning via vertex2026-09-15 00:37yes010 s
Negative framingMistral Smallmistral/mistral-small via mistral2026-09-15 00:29yes012 s
Negative framingDeepSeek V4 Flashdeepseek/deepseek-v4-flash via deepinfra2026-09-15 00:09yes059 s
Negative framingLlama 4 Maverickmeta/llama-4-maverick via bedrock2026-09-15 03:50yes01 s
Negative framingQwen 3.7 Flashalibaba/qwen3.7-flash via alibaba2026-09-15 01:47yes038 s
Negative framingKimi K2moonshotai/kimi-k2 via novita2026-09-15 04:52yes053 s
Negative framingGLM 4.7 FlashXzai/glm-4.7-flashx via zai2026-09-14 22:52yes019 s
Negative framingMiniMax M2.5minimax/minimax-m2.5 via minimax2026-09-15 04:09yes022 s

Normalization in this category

Every judgment call made between the raw labels and the numbers above, listed so it is visible and reversible.

Category-scoped readings
None. Every name in this category resolved on its own.
Unresolved, counted raw
BriteVerify / Validity Verify
BulkEmailChecker Unlimited API
BulkEmailChecker's Unlimited API
DataCaptive
Email List Verify
EmailListValidation
Emaillistchecker
MailValid
Mailgun Validate
Plauti Verify
Puzzly
Discontinued, still offered
No shut-down product was recommended here.

Also in gtm data and infrastructure

The other categories of this function, with the leader in each.
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