DevTool AI Index · 2026-11-05
Which transactional email tools do AI assistants recommend?
Asked neutral build questions about transactional email, AI assistants name Postmark most often (49% of answers on average), then SendGrid (45%). Gemini names Postmark most (62%); Claude names SendGrid most (40%).
500 neutral build questions in 25 categories, written so they never name a product. Each question is asked 3 times to every engine, because AI answers change from run to run. A share is the part of answers that names the tool. The range in brackets is a 95% interval: with fewer answers it is wider. Engines this run: Gemini, Claude (plain model answers, no web search). Run date 2026-11-05.
Top 10 tools
| # | Tool | Gemini | Claude |
|---|---|---|---|
| 1 | Postmark | 62% [49% to 73%] | 37% [26% to 49%] |
| 2 | SendGrid | 50% [38% to 62%] | 40% [29% to 53%] |
| 3 | Amazon SES | 35% [24% to 48%] | 33% [23% to 46%] |
| 4 | Mailgun | 22% [13% to 34%] | 30% [20% to 43%] |
| 5 | Resend | 30% [20% to 43%] | 20% [12% to 32%] |
| 6 | AWS SES | 22% [13% to 34%] | 7% [3% to 16%] |
| 7 | Mailjet | 5% [2% to 14%] | 5% [2% to 14%] |
| 8 | Postfix | not named | 8% [4% to 18%] |
| 9 | Mailtrap | 7% [3% to 16%] | not named |
| 10 | KumoMTA | 5% [2% to 14%] | not named |
Answers per engine: Gemini 60, Claude 60.
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Other categories
authentication · relational database hosting (Postgres/MySQL) · vector database · backend-as-a-service · frontend hosting and deployment · serverless and edge functions · payments and billing · observability and logging · error tracking · feature flags · background jobs and queues · search engine for apps · file storage and CDN · CMS (headless) · LLM API provider · AI agent framework · LLM observability and evals · web scraping and browser automation API · analytics (product) · CI/CD · infrastructure as code · realtime and websockets · maps and geocoding API · SMS and phone API