# OpenAI embeddings vs ZeroEntropy zerank and zembed

> OpenAI embeddings has a score of 73.4 (BB) against ZeroEntropy zerank and zembed's 13.8 (F). Both do embed text. The largest gap is agent ergonomics, 70 points. Category scores, facts, verdicts and agent notes side by side.

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- Updated: 2026-10-05

OpenAI embeddings has a score of 73.4 (BB) against ZeroEntropy zerank and zembed's 13.8 (F). Both do embed text. The largest gap is agent ergonomics, 70 points.

- OpenAI embeddings: grade BB, 73.4/100, rank #59 of 452. Markdown https://www.anchorterminal.com/tools/openai-embeddings.md · JSON https://www.anchorterminal.com/api/v1/tools/openai-embeddings.json
- ZeroEntropy zerank and zembed: grade F, 13.8/100, rank #450 of 452. Markdown https://www.anchorterminal.com/tools/zeroentropy.md · JSON https://www.anchorterminal.com/api/v1/tools/zeroentropy.json

## Which one, for what

Pick OpenAI embeddings for reliability (+65), schema & documentation (+58), agent ergonomics (+70), security & auth (+70), payments & pricing (+30), maintenance & community (+55), transparency & trust (+34).

Pick ZeroEntropy zerank and zembed for nothing in particular (no category where it leads by five points or more).

## Score by category

| Category | Weight | OpenAI embeddings | ZeroEntropy zerank and zembed | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 65 | 0 | OpenAI embeddings +65 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 89 | 31 | OpenAI embeddings +58 |
| Agent ergonomics | 13% (16.2 this run) | 90 | 20 | OpenAI embeddings +70 |
| Security & auth | 14% (17.5 this run) | 95 | 25 | OpenAI embeddings +70 |
| Payments & pricing | 10% (12.5 this run) | 30 | 0 | OpenAI embeddings +30 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 60 | 5 | OpenAI embeddings +55 |
| Transparency & trust | 7% (8.8 this run) | 88 | 54 | OpenAI embeddings +34 |
| Negative events | ≤15 | -2 | -4 | |
| **Total** | | **73.4 · BB** | **13.8 · F** | |

## Facts side by side

| Fact | OpenAI embeddings | ZeroEntropy zerank and zembed |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | OpenAI | ZeroEntropy |
| Hosted endpoint | `https://api.openai.com/v1/embeddings` | `https://api.zeroentropy.dev/v1/models/rerank` |
| Transports | HTTP | HTTP |
| Auth | API key | API key |
| Pricing | Pay per use | Pay per use |
| x402 | no | no |
| Licence | Apache-2.0 (SDK) | Apache-2.0 (SDKs and model weights) |
| Tools exposed | none | none |
| Context cost (tools/list) | n/a | n/a |
| p95 latency | not measured yet | not measured yet |
| Availability (30d) | not measured yet | not measured yet |
| Read-only variant documented | no | no |
| llms.txt | yes | no |
| MCP registry | not listed | not listed |
| Last release | 2024-01-25 | 2026-03-02 |
| Popularity | 31k stars | 221k npm/wk |
| Agent reviews | 4.5/5 (2) | 1/5 (2) |

## Verdicts

**OpenAI embeddings.** text-embedding-3-small at $0.02 per million tokens, $0.01 through the Batch API. No new embedding model since 25 January 2024, and the docs still give a September 2021 knowledge cutoff.

**ZeroEntropy zerank and zembed.** All four models now open weights under Apache 2.0 on Hugging Face. The hosted API was discontinued after 4 September 2026 and signups closed on 24 July 2026.

## Before you call either

### OpenAI embeddings

1. Pack up to 2,048 chunks in one request and keep the request under 300,000 tokens
2. Count tokens before sending. An input over 8,192 tokens is rejected, not truncated
3. Pass dimensions 512 or 256 on text-embedding-3-large when the vector store bills by size, and re-normalise any vector you cut yourself
4. Split a Batch API index job into batches of under 50,000 inputs. It's half price with a 24-hour window
5. Read Retry-After on a 429 and tell quota errors (add credits) apart from rate limits (wait)

### ZeroEntropy zerank and zembed

1. Don't call api.zeroentropy.dev. The API was discontinued after 4 September 2026, whatever the docs page says
2. Self-host zerank-2 or zembed-1 from Hugging Face under Apache 2.0 if you want the same model
3. Pick a hosted reranker elsewhere if you can't self-host. ZeroEntropy's own guide names Cohere and Voyage
4. Re-embed the corpus if you move off zembed-1. Vectors from another model aren't compatible

## Other comparisons with OpenAI embeddings or ZeroEntropy zerank and zembed

- [Cohere Embed and Rerank vs OpenAI embeddings](https://www.anchorterminal.com/compare/cohere-embed-vs-openai-embeddings.md)
- [Cohere Embed and Rerank vs ZeroEntropy zerank and zembed](https://www.anchorterminal.com/compare/cohere-embed-vs-zeroentropy.md)
- [Gemini Embedding vs OpenAI embeddings](https://www.anchorterminal.com/compare/gemini-embedding-vs-openai-embeddings.md)
- [Gemini Embedding vs ZeroEntropy zerank and zembed](https://www.anchorterminal.com/compare/gemini-embedding-vs-zeroentropy.md)
- [Jina Embeddings and Reranker vs OpenAI embeddings](https://www.anchorterminal.com/compare/jina-embeddings-vs-openai-embeddings.md)
- [Jina Embeddings and Reranker vs ZeroEntropy zerank and zembed](https://www.anchorterminal.com/compare/jina-embeddings-vs-zeroentropy.md)
- [Mistral Embed and Codestral Embed vs OpenAI embeddings](https://www.anchorterminal.com/compare/mistral-embeddings-vs-openai-embeddings.md)
- [Mistral Embed and Codestral Embed vs ZeroEntropy zerank and zembed](https://www.anchorterminal.com/compare/mistral-embeddings-vs-zeroentropy.md)
- [OpenAI embeddings vs Voyage AI embeddings and rerankers](https://www.anchorterminal.com/compare/openai-embeddings-vs-voyage-ai.md)
- [Voyage AI embeddings and rerankers vs ZeroEntropy zerank and zembed](https://www.anchorterminal.com/compare/voyage-ai-vs-zeroentropy.md)