Two of fourteen models named MailReach first on the direct prompt; zero named Mail-Tester. MailReach was named by eleven of the fourteen models and Mail-Tester by eleven and MailReach carries 30 labels and Mail-Tester 20, so the shares are not directly comparable.
Named in one category this edition.
Named in one category this edition.
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.
Across every category in the October 2026 Edition, MailReach and Mail-Tester were named in the same answer eighteen times, of the 62 answers naming MailReach and the 52 naming Mail-Tester. In those answers Mail-Tester took the first choice two times and MailReach two.
| Model | Direct | Paraphrase | Comparative | Budget-constrained | Scale-constrained | Negative |
|---|---|---|---|---|---|---|
| Claude Haiku 4.5 | ||||||
| GPT-5.4 mini | ||||||
| Gemini 3.5 Flash | ||||||
| Perplexity Sonar | ||||||
| Grok 4.1 Fast | ||||||
| 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 |
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.
Every negative label with a quote, up to three, then the highest-weighted positives, up to three. Five of six in this category shown.
“The tool may not accurately reflect deliverability for all B2B scenarios, so approach with caution if your audience is large or uses corporate email systems.” Mistral Small · negative prompt · soft negative
“Tools like GlockApps, MailReach, and Mailtrap vary in real-time validation depth — only some verify addresses at scale before sending.” Muse Glimmer 30B · negative prompt · soft negative
“MailReach is the best budget option for warmup and placement testing bundled into one affordable plan” Claude Haiku 4.5 · budget prompt · first choice
“or MailReach (warm‑up + testing at a lower price)” GLM 4.7 FlashX · direct prompt · first choice
“MailReach is the best overall choice in 2026” DeepSeek V4 Flash · direct prompt · first choice
Every negative label with a quote, up to three, then the highest-weighted positives, up to three. Six of eight in this category shown.
“Mail-Tester scores against a single seed address, so it can't tell you where your email lands across a multi-ISP seed network” Claude Haiku 4.5 · negative prompt · hard negative
“These are inaccurate and misleading... do not base business decisions on them.” DeepSeek V4 Flash · negative prompt · hard negative
“Avoid: Relying solely on these web-based scores. They are useful for a quick syntax check but should not be your primary deliverability testing tool.” GLM 4.7 FlashX · negative prompt · soft negative
“Mail-Tester for occasional pre-send checks of a message and its sending setup. It allows up to 3 free tests per day.” GPT-6 Luna · budget prompt · first choice
“The best email deliverability tool for a company with a limited budget is Mail-Tester or Unspam for pre-send testing” Llama 4 Maverick · budget prompt · first choice
“Start with free tools → Google Postmaster Tools + MXToolbox + Mail-Tester free tier” Kimi K2 · budget prompt · first choice
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.