# GrowthBook vs PostHog: which do AI models recommend for experimentation, October 2026

GTM AI Recommendation Index, October 2026 Edition, Experimentation and personalization. Zero of fourteen models named GrowthBook first on the direct prompt; zero named PostHog. Page: https://gtm-ai-index.com/marketing/experimentation-and-personalization/growthbook-vs-posthog/

| | First-choice share | Rank | Negative rate | Labels | Models naming it |
|---|---|---|---|---|---|
| GrowthBook | 15% | #3 of 12 | 8% | 25 | 12 of 14 |
| PostHog | 4% | #7 of 12 | 5% | 19 | 11 of 14 |

## The direct prompt, model by model

- Gemini 3.5 Flash: neither first, one named (first choices: VWO) (alternatives: Abmatic AI, Croct, Ploy, PostHog)
- Kimi K2: neither first, one named (first choices: VWO) (alternatives: Intellimize, Mutiny, PostHog)
- Claude Haiku 4.5: neither named (first choices: VWO) (alternatives: Mutiny)
- GPT-5.4 mini: neither named (first choices: Kameleoon) (alternatives: Optimizely Web Experimentation, VWO Testing)
- Perplexity Sonar: neither named (first choices: VWO) (alternatives: Personyze)
- Grok 4.1 Fast: neither named (first choices: VWO) (alternatives: AB Tasty, Convert Experiences, Mutiny)
- Mistral Small: neither named (first choices: Optimizely Web Experimentation, Personyze) (alternatives: Kameleoon)
- DeepSeek V4 Flash: neither named (first choices: Convert Experiences, Mutiny) (alternatives: Abmatic AI, VWO)
- Llama 4 Maverick: neither named (first choices: Optimizely Web Experimentation) (alternatives: HubSpot, Kameleoon, Personyze)
- Qwen 3.7 Flash: neither named (first choices: VWO) (alternatives: AB Tasty, Convert Experiences, Mutiny)
- GLM 4.7 FlashX: neither named (first choices: Mutiny) (alternatives: Abmatic AI, VWO)
- MiniMax M2.5: neither named (first choices: Markettailor, VWO) (alternatives: AB Tasty, Mutiny)
- GPT-6 Luna: neither named (first choices: VWO) (alternatives: Optimizely CMS)
- Muse Glimmer 30B: neither named (first choices: Mutiny, VWO) (alternatives: HubSpot, Kameleoon, Personyze)

## What the models said about GrowthBook

- "requiring less technical overhead than developer-heavy solutions like GrowthBook" (Qwen 3.7 Flash, paraphrase prompt, soft negative)
- "Open-source, requires more technical setup" (Kimi K2, scale prompt, soft negative)
- "GrowthBook and PostHog are free to start, and both are open-source so that you can self-host them, making them excellent choices if you want zero upfront costs." (Claude Haiku 4.5, budget prompt, first choice)
- "The Alternative: If your program is engineering-led, opt for server-side testing or warehouse-native platforms (such as GrowthBook, Eppo, or PostHog)" (Gemini 3.5 Flash, negative prompt, first choice)
- "GrowthBook is open-source A/B testing and feature-flagging platform, and it is the pick when budget is your tightest constraint." (Muse Glimmer 30B, budget prompt, first choice)

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. Comparisons are drawn for the top eight products in each category. Published under CC BY 4.0; the output is the models' output, and nothing here is a recommendation by the index.