# Chroma vs MongoDB Atlas Vector Search: which do AI models recommend for vector databases, October 2026

IT AI Recommendation Index, October 2026 Edition, Vector databases. Zero of fourteen models named Chroma first on the direct prompt; zero named MongoDB Atlas Vector Search. Page: https://it-ai-index.com/it-data/vector-databases/chroma-vs-mongodb-atlas-vector-search/

| | First-choice share | Rank | Negative rate | Labels | Models naming it |
|---|---|---|---|---|---|
| Chroma | 6% | #4 of 10 | 31% | 36 | 14 of 14 |
| MongoDB Atlas Vector Search | 2% | #7 of 10 | 8% | 12 | 8 of 14 |

## The direct prompt, model by model

- Qwen 3.7 Flash: neither first, one named (first choices: Pinecone) (alternatives: MongoDB Atlas Vector Search, Weaviate)
- Claude Haiku 4.5: neither named (first choices: Pinecone, Weaviate)
- GPT-5.4 mini: neither named (first choices: Pinecone) (alternatives: Qdrant, Weaviate)
- Gemini 3.5 Flash: neither named (first choices: pgvector) (alternatives: Pinecone, Qdrant, Weaviate)
- Perplexity Sonar: neither named (first choices: Qdrant, pgvector) (alternatives: Pinecone, Weaviate)
- Grok 4.1 Fast: neither named (first choices: pgvector) (alternatives: Pinecone, Qdrant, Weaviate)
- Mistral Small: neither named (first choices: pgvector) (alternatives: pgvectorscale)
- DeepSeek V4 Flash: neither named (first choices: Qdrant, pgvector) (alternatives: Pinecone, Weaviate)
- Llama 4 Maverick: neither named (first choices: pgvector)
- Kimi K2: neither named (first choices: pgvector) (alternatives: Pinecone, Qdrant, Weaviate)
- GLM 4.7 FlashX: neither named (first choices: Qdrant, Weaviate) (alternatives: pgvector)
- MiniMax M2.5: neither named (first choices: Pinecone) (alternatives: Elasticsearch, Milvus, Weaviate)
- GPT-6 Luna: neither named (first choices: Qdrant) (alternatives: Pinecone, pgvector)
- Muse Glimmer 30B: neither named (first choices: Pinecone, pgvector) (alternatives: Qdrant, Weaviate)

## What the models said about Chroma

- "Chroma has experienced significant production issues, including a critical memory leak... A severe cache invalidation bug in version 0.5 caused p99 latency to spike from 42ms to 542ms" (MiniMax M2.5, negative prompt, hard negative)
- "Only use Chroma behind a private network with auth enabled and patched, never internet exposed with defaults." (Muse Glimmer 30B, negative prompt, hard negative)
- "Avoid Chroma for production — it's a prototype tool, not a production database" (Kimi K2, negative prompt, hard negative)
- "Start with Chroma or Qdrant (self‑hosted) or pgvector if you already have PostgreSQL." (GLM 4.7 FlashX, budget prompt, first choice)
- "Best for small budgets: Chroma (free, self-hosted) or pgvector (free, if using PostgreSQL)." (Mistral Small, budget prompt, first choice)
- "Chroma: Offers a free plan and is considered one of the cheapest options." (Llama 4 Maverick, budget prompt, first choice)

## What the models said about MongoDB Atlas Vector Search

- "MongoDB Atlas gets pricing gripes in broader DB contexts" (Grok 4.1 Fast, negative prompt, soft negative)
- "the sweet spot today is MongoDB Atlas Vector Search (if your data already lives in MongoDB)" (GLM 4.7 FlashX, paraphrase prompt, first choice)
- "Stick with MongoDB Atlas if your existing data pipeline is already built around MongoDB documents." (Qwen 3.7 Flash, direct prompt, alternative)
- "Use pgvector or Atlas Vector Search" (Kimi K2, scale prompt, alternative)

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.