[Blog](https://supermemory.ai/blog) · [Learning](https://supermemory.ai/blog/tag/learning)

# Choosing Open Embedding Models: A Reproducible Retrieval Evaluation

Compare embedding models using their documented prompts, licenses, dimensions, and measured performance on your own retrieval tasks.

By Shardul Mane June 27, 2025 · 3 min read 

![Choosing Open Embedding Models: A Reproducible Retrieval Evaluation](https://supermemory.ai/_astro/cover.Di11VIaE_ZeJ59J.webp)

Choose an embedding model by testing retrieval on the questions and documents your application actually uses. A leaderboard result, vector dimension, or model size helps form a shortlist; none establishes the best model for every corpus.

Start with BGE, E5, Nomic and MiniLM as reference models for the evaluation below. Fix the dataset, model revision, preprocessing and hardware so differences in accuracy or latency can guide your choice.

## Build a shortlist from model cards

| Candidate | What to check before running                                         |
| --------- | -------------------------------------------------------------------- |
| BGE       | Retrieval instruction, language coverage, normalization, revision    |
| E5        | Distinct query and passage prefixes, truncation, normalization       |
| Nomic     | Task prefixes, context handling, revision-specific dimension support |
| MiniLM    | Input truncation, domain fit, embedding dimension and license        |

Start with the official cards for [BGE base English v1.5](https://huggingface.co/BAAI/bge-base-en-v1.5), [E5 base v2](https://huggingface.co/intfloat/e5-base-v2), [Nomic text v1.5](https://huggingface.co/nomic-ai/nomic-embed-text-v1.5), and [all-MiniLM-L6-v2](https://huggingface.co/sentence-transformers/all-MiniLM-L6-v2). Use their documented input requirements to build a baseline before testing additional models.

Open weights do not mean inference, hosting, or maintenance is free. Check the license and deployment constraints for each exact revision before adopting it. Avoid assuming that every model in a family has the same terms or input contract.

## Get preprocessing right before comparing scores

For asymmetric retrieval, E5's documented recipe distinguishes queries from passages. Missing the required prefixes can invalidate a comparison. Use this helper to add the appropriate prefix before encoding:

```
def e5_input(text, kind):
    if not isinstance(text, str) or not text.strip():
        raise ValueError("Text is required")
    if kind not in ("query", "passage"):
        raise ValueError("kind must be query or passage")
    return kind + ": " + text.strip()
```

Do not apply that exact recipe to every model. Follow each card's instructions, use the same document content, and record truncation. If one encoder silently drops the relevant sentence, the comparison is partly testing input handling rather than semantic quality.

## Fix the evaluation data

Create questions with labeled supporting document or chunk IDs. Include exact identifiers, paraphrases, domain terminology, ambiguous follow-ups, and questions with no supporting evidence. Keep a held-out set that is not used to tune thresholds or select prompts.

Record the corpus version and chunking strategy. A model tested on full documents cannot be compared fairly with another tested on carefully selected answer-sized chunks without explaining that difference.

Use a representative workload first. A public biomedical dataset may be useful for a specific experiment, but it cannot establish performance for your support tickets or code repository by itself.

## Measure retrieval, then the answer

Candidate recall measures whether supporting evidence enters the pool. Rank-sensitive metrics measure where it appears. The [reranking guide](https://supermemory.ai/blog/contextual-reranking-for-rag/) includes a Python helper for calculating recall and reciprocal rank.

Measure answer support separately using the same answer model and prompt. A better retrieval score can fail to improve answers if context assembly truncates the evidence or the answer model ignores it. Likewise, an answer may look correct from prior model knowledge despite retrieving nothing useful.

## Make latency and cost comparable

Report document-encoding throughput separately from query latency. Record batching, concurrency, device, precision, warm-up, cache state, and input lengths. For a remote service, record the region and include network time if that is what users experience.

Include index storage, updates, re-embedding, and operational work in the cost model. If a model change requires regenerating every stored vector, the migration cost belongs in the decision. A smaller vector may reduce raw storage without reducing encoder inference cost proportionally.

## Publish the evidence with the conclusion

Keep model revision IDs, preprocessing code, question labels, ranked results, metric definitions, and run configuration with any reported ranking. Label a small pilot as a pilot and keep unavailable results missing rather than treating them as zero.

For dimension-specific tradeoffs, use the [Matryoshka guide](https://supermemory.ai/blog/matryoshka-representation-learning-the-ultimate-guide-how-we-use-it/). For the full pipeline, start with the [RAG tutorial](https://supermemory.ai/blog/how-to-build-rag-based-chatbot-guide/).

If you would rather evaluate a managed retrieval service alongside the model shortlist, [start a Supermemory pilot](https://console.supermemory.ai/) with the same corpus and questions. Compare supported answers and total operating cost separately from the embedding-only scores.

## Other posts.

1. [We're open sourcing the company brain. Here's how we designed the multiplayer harness Company Brain is now open source. A walkthrough of the multiplayer harness behind its Slack experience, from proactivity and memory boundaries to approvals and recovery. NewsSep 25, 2026 ](https://supermemory.ai/blog/open-sourcing-company-brain)
2. [Jev changes a lot in memory & context engineering. Here's exactly how. We tested Jev across reranking, chunking, observation, and harness decisions. Here is where fast decision models help memory systems, where they cost more, and where they still fall short. EngineeringSep 24, 2026 ](https://supermemory.ai/blog/jev-memory-context-engineering)
3. [I reverse-engineered Instinct's memory. Here's exactly how it works Instinct keeps its memory as git-tracked markdown files, found with grep rather than vectors. Here is the whole system as far as black-box probing can reconstruct it, and how to rebuild it on supermemory in about 60 lines. EngineeringSep 20, 2026 ](https://supermemory.ai/blog/reverse-engineering-instinct-memory)
4. [An update to supermemory We've discontinued the supermemory company brain and Nova. Everyone who was charged has been refunded, our MCP and plugins continue to run, and we're going all in on the memory engine. NewsSep 10, 2026 ](https://supermemory.ai/blog/an-update-to-supermemory)
5. [Scaling Conversations: How Adapta Grew Usage Without Losing Context Adapta added Supermemory as a persistent memory layer so every conversation keeps its context — letting the team scale usage without losing the thread. Case StudyJun 12, 2026 ](https://supermemory.ai/blog/adapta-scaling-conversations)
6. [How Chatarmin Ditched RAG and Went Memory-Only with Supermemory Chatarmin replaced a heavy RAG pipeline with Supermemory's memory layer — cutting average AI response time from 40s to 12s and token usage by 40–50%. Case StudyJun 10, 2026 ](https://supermemory.ai/blog/chatarmin-memory-only)
7. [SMFS: making agentic retrieval 55% cheaper AND more accurate We launched SMFS.ai (Supermemory Filesystem) a few weeks ago, with a simple bet: We can redesign the filesystem specifically for agents, with special files, structures, and commands that it can use for it's tasks. Today, SMFS is used by hundreds of companies to power their agents. EngineeringMay 28, 2026 ](https://supermemory.ai/blog/smfs-making-agentic-retrieval-55-cheaper-and-more-accurate)
8. [Introducing Dynamic Dreaming: supermemory now connects the dots, for you. Dreaming is magical. TLDR: We're launching Dynamic Dreaming in supermemory today, which automatically works if you're using supermemory in any way - API, OpenClaw, Hermes agent, etc. EngineeringMay 25, 2026 ](https://supermemory.ai/blog/introducing-dynamic-dreaming-supermemory-now-connects-the-dots-for-you)
9. [Dear reader, we just made supermemory insanely cheap... the Context Cloud When I first started building supermemory, I had one goal: To build the best memory system for AI. I would talk to customers, and find out that memory was not the only thing they needed - They were all setting up 7-8 different vendors at the same time. EngineeringMay 18, 2026 ](https://supermemory.ai/blog/dear-reader-we-just-made-supermemory-insanely-cheap-the-context-cloud)
10. [Introducing @supermemory/tools v2.0.0 Today we're releasing v2.0.0\. This release unifies the API across all agents sdk integrations from AI SDK to Mastra, makes conversation identity a first-class concept, and ships with memory saving on by default. EngineeringApr 27, 2026 ](https://supermemory.ai/blog/introducing-supermemory-tools-v2-0-0)
11. [Solving the Precision-Recall Tradeoff: Search Result Aggregation When you're building memory for AI, search is your foundational layer. The way search generally works is straightforward: the user defines a query, and then sets a limit (top-K) on how many search results they want returned. Usually, this is set to 10 or 20. EngineeringApr 5, 2026 ](https://supermemory.ai/blog/solving-the-precision-recall-tradeoff-search-result-aggregation)
12. [OpenClaw Memory Problems: Why It Forgets and How to Fix It (2026) TLDR: Today, we are releasing a new version of our openclaw plugin - https://github.com/supermemoryai/openclaw-supermemory. This post is going to be a bit technical, so bear with me (or bookmark for later!) In this post, I will talk about what we do about OpenClaw memory, and how we fix it. EngineeringFeb 19, 2026 ](https://supermemory.ai/blog/why-everyone-is-complaining-about-openclaws-memory-it-sucks-and-why-supermemory-fixes-it)
13. [Stateful Coding Agents with Memory: Build Long-Running Agents (2026) We built a plugin for Claude Code and OpenCode that gives your coding agent persistent memory. It remembers your preferences, learns your codebase, and never loses context mid-conversation. The result is an agent you can run for months without starting over. EngineeringFeb 18, 2026 ](https://supermemory.ai/blog/infinitely-running-stateful-coding-agents)
14. [Clawd / Molt bot's memory SUCKS. We gave it supermemory. I'm the founder of supermemory. Clawd/Molt bot is blowing up right now, with many, many use cases. I set it up, too, and have been using it through telegram. TLDR: just go to https://supermemory.ai/docs/integrations/clawdbot to set up supermemory for your clawd bot. EngineeringJan 28, 2026 ](https://supermemory.ai/blog/clawd-molt-bots-memory-sucks-we-gave-it-supermemory)
15. [Catch up with our UNFORGETTABLE Launch Week Over the last year, one belief has guided almost everything we’ve built at Supermemory AI becomes meaningfully useful only when it remembers. Memory shouldn’t be something developers rebuild from scratch. It shouldn’t be fragile, expensive, or trapped inside a single tool. NewsJan 4, 2026 ](https://supermemory.ai/blog/catch-up-with-our-unforgettable-launch-week)
16. [Empowering the Next Generation of Founders: Supermemory Startup Program If there’s one thing we’ve learned while building Supermemory, it’s that most startups don’t fail because they didn't build features; they fail when infrastructure slows them down, or they built too slow. NewsDec 31, 2025 ](https://supermemory.ai/blog/empowering-the-next-generation-of-founders-supermemory-startup-program)
17. [Building code-chunk: AST Aware Code Chunking At Supermemory, we're building context engineering infrastructure for AI. A huge part of that is dealing with code: ingesting repos, understanding structure, and making it searchable. The problem is that most code chunking solutions are terrible. We built code-chunk to fix this. EngineeringDec 29, 2025 ](https://supermemory.ai/blog/building-code-chunk-ast-aware-code-chunking)
18. [Supermemory raises $3 million with the best memory engine for LLMs Today, I am excited to announce our first funding round to accelerate our mission of building an interoperable, scalable and reliable memory for LLMs and agents. Memory is one of the hardest challenges in AI right now. NewsOct 6, 2025 ](https://supermemory.ai/blog/supermemory-raises-3-million-and-building-the-best-memory-engine-for-llms)
19. [Mem0 vs Supermemory: Why Scira Switched Scira AI moved its production memory layer from Mem0 to Supermemory. This is what failed, what improved, and how the team evaluated the two systems. Case StudyOct 2, 2025 ](https://supermemory.ai/blog/why-scira-ai-switched)
20. [Never Record Again: How Montra Uses Supermemory to Rethink Video Creation Campbell Baron, the founder of Montra, has been making videos since he was twelve. By thirteen, he was already doing brand work. Today, he’s betting on a very different future for creators: a world where recording is the exception, and most videos are generated from scratch. Case StudyAug 21, 2025 ](https://supermemory.ai/blog/never-record-again-how-montra-uses-supermemory-to-rethink-video-creation)
21. [Unified Memory That Works Where You Work: Your Second Brain With Supermemory Hi everyone, I’m Dhravya, the founder of Supermemory. I want to start with a little story behind why this product means so much to me. You can also skip straight to what it is and how it works below. EngineeringJul 25, 2025 ](https://supermemory.ai/blog/unified-memory-that-works-where-you-work-your-second-brain-with-supermemory)
22. [Supermemory just got faster on PlanetScale What is Supermemory? Supermemory completes the missing part of the LLM puzzle: memory. Just as memory is crucial for human intelligence, it's essential for truly intelligent AI systems. EngineeringJul 18, 2025 ](https://supermemory.ai/blog/supermemory-just-got-faster-on-planetscale)
23. [Faster, smarter, reliable infinite chat: Supermemory IS context engineering. People are obsessed with prompts and prompt engineering. Sure, what you say is important, but what the model knows when you say it is the difference between a stateless text generator and an intelligent AI system. In short, context is the most crucial component. NewsJul 9, 2025 ](https://supermemory.ai/blog/faster-smarter-reliable-infinite-chat-supermemory-is-context-engineering)
24. [We solved AI API interoperability One API to rule them all, One spec to find them, One library to bring them all and in the TypeScript, bind them. When we were building the Infinite Chat API, initially, we only supported the OpenAI format. This was fine, until a lot of our customers started asking for more. EngineeringJul 7, 2025 ](https://supermemory.ai/blog/we-solved-ai-api-interoperability)
25. [The Wow Factor of Memory - How Flow Used Supermemory To Build Smarter, Stickier Products Overview: Flow is a note-taking app built around a bold vision: to create a more personal, context-aware writing experience powered by AI. At the heart of this mission is memory. Case StudyJun 14, 2025 ](https://supermemory.ai/blog/the-wow-factor-of-memory-how-flow-used-supermemory-to-build-smarter-stickier-products)
26. [The UX and technicalities of awesome MCPs Last month, we launched the Supermemory MCP, mostly to test our own infrastructure and get some initial traction. It blew up. To my absolute surprise, the initial launch itself got half a million impressions (!!!). Then, we launched and got #2 on ProductHunt too. EngineeringJun 8, 2025 ](https://supermemory.ai/blog/the-ux-and-technicalities-of-awesome-mcps)
27. [Architecting a memory engine inspired by the human brain Language is at the heart of intelligence, but what truly powers meaningful interaction is memory — the ability to accumulate, recall, and contextualize information over time. Large Language Models (LLMs) have mastered language, but memory remains their Achilles’ heel. EngineeringJun 5, 2025 ](https://supermemory.ai/blog/memory-engine)

## Start building with supermemory.

Memory and continual learning for any model, any harness. Available through our API, plugins, and MCP.

[Build with supermemory ](https://console.supermemory.ai/)