Email verification
Asked as “email verification service”, and as “email list validation tool”, on behalf of a mid-market B2B software company. 55 first choices recorded across the direct, paraphrase, budget and scale prompts, six models each.
Standing · first-choice share
42%
Clear leader
42ZeroBounce22Bouncer09MillionVerifier27others
42% of first choices, clear leader.
Since September 2026▲+12Since September 2026: 29% → 42%, +12 points. Past the 12-point floor: movement. Read over the models both editions asked.ZeroBounce held the lead, +12 points on 29%, past the floor.
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
01
ZeroBounce42%3%63endorsed leader▲+12Since September 2026: 29% → 42%, +12 points. Past the 12-point floor: movement. Read over the models both editions asked.29% → 42%
ZeroBounce42%3%63endorsed leader▲+12Since September 2026: 29% → 42%, +12 points. Past the 12-point floor: movement. Read over the models both editions asked.29% → 42%02
Bouncer22%0%52accepted challenger▼−1Since September 2026: 24% → 23%, −1 point. Inside the 12-point floor: within noise. Read over the models both editions asked.24% → 23%
Bouncer22%0%52accepted challenger▼−1Since September 2026: 24% → 23%, −1 point. Inside the 12-point floor: within noise. Read over the models both editions asked.24% → 23%03
MillionVerifier9%30%20criticized challenger▲+8Since September 2026: 0% → 8%, +8 points. Inside the 12-point floor: within noise. Read over the models both editions asked.0% → 8%
MillionVerifier9%30%20criticized challenger▲+8Since September 2026: 0% → 8%, +8 points. Inside the 12-point floor: within noise. Read over the models both editions asked.0% → 8%04
NeverBounce4%8%49accepted challenger▲+2Since September 2026: 2% → 4%, +2 points. Inside the 12-point floor: within noise. Read over the models both editions asked.2% → 4%
NeverBounce4%8%49accepted challenger▲+2Since September 2026: 2% → 4%, +2 points. Inside the 12-point floor: within noise. Read over the models both editions asked.2% → 4%05
Hunter Email Verifier4%7%29accepted challenger▼−6Since September 2026: 10% → 4%, −6 points. Inside the 12-point floor: within noise. Read over the models both editions asked.10% → 4%
Hunter Email Verifier4%7%29accepted challenger▼−6Since September 2026: 10% → 4%, −6 points. Inside the 12-point floor: within noise. Read over the models both editions asked.10% → 4%06
DeBounce4%15%20accepted challenger▼−2Since September 2026: 4% → 2%, −2 points. Inside the 12-point floor: within noise. Read over the models both editions asked.4% → 2%
DeBounce4%15%20accepted challenger▼−2Since September 2026: 4% → 2%, −2 points. Inside the 12-point floor: within noise. Read over the models both editions asked.4% → 2%07
EmailListVerify4%18%17accepted challenger=heldSince September 2026: 4% → 4%, ±0 points. Inside the 12-point floor: within noise. Read over the models both editions asked.4% → 4%
EmailListVerify4%18%17accepted challenger=heldSince September 2026: 4% → 4%, ±0 points. Inside the 12-point floor: within noise. Read over the models both editions asked.4% → 4%Show the three products at 0%, ordered by negative rate
08
Kickbox0%0%34accepted challenger▼−4Since September 2026: 4% → 0%, −4 points. Inside the 12-point floor: within noise. Read over the models both editions asked.4% → 0%
Kickbox0%0%34accepted challenger▼−4Since September 2026: 4% → 0%, −4 points. Inside the 12-point floor: within noise. Read over the models both editions asked.4% → 0%10
Clearout0%0%22accepted challenger▼−6Since September 2026: 6% → 0%, −6 points. Inside the 12-point floor: within noise. Read over the models both editions asked.6% → 0%
Clearout0%0%22accepted challenger▼−6Since September 2026: 6% → 0%, −6 points. Inside the 12-point floor: within noise. Read over the models both editions asked.6% → 0%09
Emailable0%0%22accepted challenger=heldSince September 2026: 0% → 0%, ±0 points. Inside the 12-point floor: within noise. Read over the models both editions asked.0% → 0%
Emailable0%0%22accepted challenger=heldSince September 2026: 0% → 0%, ±0 points. Inside the 12-point floor: within noise. Read over the models both editions asked.0% → 0%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 is noise, and both are shown. 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 →
01020304050607080910Accepted challengerEndorsed leader
0%First-choice share → · lines at 30% share and 25% negative60%
Key
01ZeroBounce42%
ZeroBounce42%02Bouncer22%
Bouncer22%03MillionVerifier9%
MillionVerifier9%04NeverBounce4%
NeverBounce4%05Hunter Email Verifier4%
Hunter Email Verifier4%06DeBounce4%
DeBounce4%07EmailListVerify4%
EmailListVerify4%08Kickbox0%
Kickbox0%09Emailable0%
Emailable0%10Clearout0%
Clearout0%What they warned about
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.
MillionVerifier30%
6 of 20 labels negative · 5 of 6 models · 1 hard negative
“MillionVerifier is the one most often singled out with documented false positives and billing complaints — proceed with caution there.” DeepSeek V4 Flash, negative prompt
EmailVerify.io
100%
3 of 3 labels negative · 3 of 6 models · 2 hard negative
“Some users report it as a "complete scam" - Complaints about taking money without working” Kimi K2, negative prompt
NeverBounce8%
4 of 49 labels negative · 3 of 6 models · 1 hard negative
“After being acquired by ZoomInfo, NeverBounce has faced significant backlash... Price Hikes... Expiring Credits” Gemini 3.5 Flash, negative prompt
EmailListVerify18%
3 of 17 labels negative · 3 of 6 models
“Budget/low-cost options like EmailListVerify, MillionVerifier, and DeBounce** - **Approach with caution**” Grok 4.20, negative prompt
What they cite
Citations exist only for the models that return a source list: fourteen of the six in this edition.
Sites the answers cite
77 of 84 answers in this category came back with a source list, from 14 of 6 models: citations where the model returns them, or the search results it consulted. 997 links across 193 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.
41 answers · 59 citations · 12 models
vendor site · Kickbox41 answers · 54 citations · 11 models
vendor site · Overloop34 answers · 34 citations · 11 models
vendor site · Sender32 answers · 38 citations · 11 models
vendor site · ZoomInfo25 answers · 44 citations · 10 models
vendor site · ZeroBounce25 answers · 36 citations · 11 models
vendor site · Sparkle.io24 answers · 33 citations · 10 models
22 answers · 23 citations · 10 models
vendor site · Instantly19 answers · 20 citations · 8 models
vendor site · Prospeo18 answers · 30 citations · 9 models
vendor site · Hunter18 answers · 19 citations · 11 models
17 answers · 17 citations · 9 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.
32 answers · 11 models
30 answers · 11 models
25 answers · 11 models
22 answers · 10 models
18 answers · 10 models
17 answers · 10 models
17 answers · 9 models
17 answers · 9 models
16 answers · 11 models
16 answers · 8 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 |
|---|---|---|---|---|---|---|---|---|
| ZeroBounce zerobounce.net | 42% | 203 | 9,900 | 118 | 38,183 | $778 | 120 | 2 |
| Bouncer usebouncer.com | 22% | 140 | 27,100 | 6,621 | 9,553 | 24 | 6 | |
| MillionVerifier millionverifier.com | 9% | 52 | 1,900 | 1 | 1,260 | 4 | ||
| NeverBounce neverbounce.com | 4% | 144 | 8,100 | 64 | 73,301 | 16 | ||
| Hunter Email Verifier hunter.io | 4% | 79 | 5,400 | 0 | 152,782 | 6 | 5 | |
| DeBounce debounce.com | 4% | 45 | 3,600 | 661 | 4,116 | |||
| EmailListVerify emaillistverify.com | 4% | 39 | 480 | 1 | 11,192 | 24 | ||
| VerifiedEmail verified.email | 4% | 6 | ||||||
| Snov.io snov.io | 2% | 66 | 3,600 | 71 | 46,528 | 3 | ||
| Findymail findymail.com | 2% | 12 |
Google's top ten for the two searches hold 16 sites; 4 of them are among the sites the models cited here (emailvendorselection.com, hunter.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 company?”Paraphrase“Which email list validation tool would you recommend to a mid-sized B2B 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 5no first choiceno first choiceno first choiceno first choiceno first choicenothing named
Claude Opus 4.8no first choiceno first choiceno first choiceno first choiceno first choicenothing named
GPT-6 Astrano first choiceno first choiceno first choiceno first choiceno first choicenothing named
GPT-5.6 Solno first choiceno first choiceno first choiceno first choiceno first choicenothing named
Gemini 3.1 Prono first choiceno first choiceno first choiceno first choiceno first choicenothing named
Perplexity Sonar Prono first choiceno first choiceno first choiceno first choiceno first choicenothing named
Bold 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. Full answer text is in the free responses file. Download the record
Zero rows: every prompt, every model, every answer.
| Prompt | Model | Version string | Time (UTC) | Searched | Sources | Latency |
|---|
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
Bulk Email Checker read as BulkEmailChecker
Hunter read as Hunter Email Verifier
Hunter (Email Finder & Verifier) read as Hunter Email Verifier
Hunter (Email Verifier) read as Hunter Email Verifier
Hunter.io read as Hunter Email Verifier
Validity (BriteVerify) read as Validity BriteVerify
Unresolved, counted raw
Abstract API
Bounceless.io
EmailListCleaner.org
Kickback.ai
MailCleanup
MailVeri
Mailboxlayer
RevealAB
Scrubby
SimpleVerifier
Unspam Email Verifier
UseBouncer
Verifio
Verifly
email-verifier (Go)
truemail.io
Discontinued, still offered
No shut-down product was recommended here.