Email deliverability and testing tools · November 2026 Edition
ZeroBounce vs MXToolbox
Two of fourteen models named ZeroBounce first on the direct prompt; zero named MXToolbox. ZeroBounce was named by thirteen of the fourteen models and MXToolbox by thirteen and ZeroBounce carries 28 labels and MXToolbox 32, so the shares are not directly comparable.
Named in four categories this edition.
Named in one category this edition.
First-choice share4%2%Of first choices across the direct, paraphrase, budget and scale prompts, 0 to 100.
Negative rate14%6%Negative labels as a share of the product's labels, 0 to 100.
Rank in category#4#5A position in a field of 19; printed, not drawn.
Labels2832A count; the two differ.
The two percentage rows are drawn on one 0 to 100 track, ZeroBounce reading right to left. Rank and label count are printed, not drawn.GlockApps was named alongside these two in twelve of the fourteen direct answers. GlockApps vs ZeroBounce · GlockApps vs MXToolbox · Google Postmaster Tools vs ZeroBounce
Share is the count of first choices across the direct, paraphrase, budget and scale prompts over all fourteen models, for a mid-market B2B company; rank is within the category; every quote names the model and the prompt it came from. Both figures come from the email deliverability and testing tools page.
By framing
How many of the fourteen models made each the first choice, per way of asking, and how many argued against it.
ZeroBounceFirst choices, of fourteen modelsMXToolbox
Direct201 against ZeroBounce
Paraphrase00
Comparative01
Budget-constrained011 against ZeroBounce
Scale-constrained00
Negative012 against ZeroBounce · 2 against MXToolbox
Bars are first choices, 0 to 14 each sideModels that argued againstA model can name both, so the two sides of a row do not sum to fourteen.
Every model, every framing
The eighty-four answers behind the chart above, one cell each: where ZeroBounce and MXToolbox stood in it.
| Model | Direct | Paraphrase | Comparative | Budget-constrained | Scale-constrained | Negative |
|---|---|---|---|---|---|---|
| Claude Haiku 4.5 | | |||||
| GPT-5.4 mini | | | ||||
| Gemini 3.5 Flash | | | | |||
| Perplexity Sonar | | | | | ||
| Grok 4.20 | | | | | ||
| Mistral Small | | | | |||
| DeepSeek V4 Flash | | | | | ||
| Llama 4 Maverick | ||||||
| Qwen 3.7 Flash | | | ||||
| Kimi K2 | | | | |||
| GLM 4.7 FlashX | | | ||||
| MiniMax M2.5 | | | | | ||
| GPT-6 Luna | | |||||
| Muse Glimmer 30B | | | | | |
ZeroBounce MXToolbox first choice named as an alternative argued againstblank: not namedEach cell is one answer, ZeroBounce on the left and MXToolbox on the right.The direct prompt
The plain question, one answer per model, grouped by where ZeroBounce and MXToolbox stood in it.
ZeroBounce first, MXToolbox an alternative
2 of 14 modelsMXToolbox was named in the answer but not as the choice, or not at all.Qwen 3.7 FlashGlockApps, ZeroBounce alternatives: Kickbox, NeverBounce, Red Sift OnDMARC, SendForensics, Suped, Validity Everest
MiniMax M2.5HubSpot Sales Hub, ZeroBounce alternatives: Copper, GlockApps, MXToolbox
Neither was the first choice, one was named
2 of 14 modelsThe answer put something else first and named one of the two as an alternative.GPT-5.4 miniLitmus alternatives: Brevo, HubSpot, Salesforce/Marketing Cloud, ZeroBounce
Perplexity SonarGlockApps alternatives: EasyDMARC, Google Postmaster Tools, MailReach, Microsoft SNDS, NeverBounce, Validity Everest, ZeroBounce, dmarcian
Neither was named
10 of 14 modelsThe answer made no first choice from these two in this category.Claude Haiku 4.5Warmy alternatives: Act-On, GlockApps, MailReach, Mailtrap Email Marketing
Gemini 3.5 FlashGlockApps alternatives: Folderly, Google Postmaster Tools, Mailgun Optimize, Mailtrap Email Sandbox, Microsoft Smart Network Data Services (SNDS) / Microsoft 365 Admin Insights
Grok 4.20GlockApps alternatives: Allegrow, Validity Everest
Mistral SmallAllegrow, Validity Everest alternatives: Litmus
DeepSeek V4 FlashHubSpot Sales Hub alternatives: GlockApps, Klaviyo, Lemlist, Mailgun, Outreach, Salesloft, SendGrid
Llama 4 MaverickGlockApps alternatives: MailReach, Validity Everest
Kimi K2Allegrow alternatives: GlockApps, MailReach
GLM 4.7 FlashXGlockApps alternatives: Allegrow, MailReach
GPT-6 LunaGlockApps alternatives: Google Postmaster Tools, Validity Engage
Muse Glimmer 30BGlockApps, MailGenius alternatives: Allegrow, Amplemarket
Bold names in an answer are the products the judge labeled a first choice; a model naming several gives each of them that label. The full answer text for every row is in the record.
By buyer segment
The same question asked on behalf of a different buyer. Each standing is computed within its segment and they are never added together. The figures above are the mid-market standing, which is the one the category orders by.
Small business
MXToolbox leads by five points.
MXToolbox5%#6 of 15ZeroBounce0%#12 of 15Mid-marketThe figures above
The order flips: ZeroBounce leads at mid-market.
ZeroBounce4%#4 of 19MXToolbox2%#5 of 19Enterprise
ZeroBounce leads by two points.
ZeroBounce2%#9 of 17MXToolbox0%#16 of 17What the models said about ZeroBounce
Every negative label with a quote, up to three, then the highest-weighted positives, up to three. Two of two in this category shown.
“Address-verification services such as ZeroBounce, Kickbox, or comparable vendors: treat results as risk estimates, not proof of consent” Perplexity Sonar · negative prompt · soft negative
“"Valid" emails bouncing (both soft and hard bounces); precision issues with certain domains” Kimi K2 · negative prompt · soft negative
What the models said about MXToolbox
Every negative label with a quote, up to three, then the highest-weighted positives, up to three. Five of six in this category shown.
“Blocklist-only monitors such as MXToolbox or Heatwave: a clean result does not mean good deliverability” Perplexity Sonar · negative prompt · soft negative
“basic free blocklist checkers (in isolation) ... Over-reliance can give false confidence.” Grok 4.20 · negative prompt · soft negative
“start with Google Postmaster Tools and MXToolbox, which are both free and cover the most common starting points” Claude Haiku 4.5 · budget prompt · first choice
“Use free tools (Google Postmaster, MXToolbox, Microsoft SNDS) for monitoring” MiniMax M2.5 · negative prompt · first choice
“Start with free tools like MXToolbox and Google Postmaster for diagnostics.” Grok 4.20 · comparative prompt · first choice
Also compared
GlockApps vs ZeroBounceGlockApps vs MXToolboxGoogle Postmaster Tools vs ZeroBounceGoogle Postmaster Tools vs MXToolboxLitmus vs ZeroBounceLitmus vs MXToolboxZeroBounce vs MailReachZeroBounce vs Validity EverestZeroBounce vs Mail-TesterMXToolbox vs MailReachMXToolbox vs Validity EverestMXToolbox vs Mail-TesterAll twenty-eight head-to-head pages and the full email deliverability standing
Comparisons are drawn for the top eight products in each category, each against each. The output is the models' output; nothing here is a recommendation by the index.