Head to head · Text embeddings · October 2026 research run

Qwen3-Embedding-0.6B vs Qwen3-Embedding-4B

Qwen3-Embedding-4B scores 72.9 (BB) on agent readiness against Qwen3-Embedding-0.6B's 63.5 (B), and leads in 2 of 5 scored categories. Qwen3-Embedding-0.6B leads on documentation and upkeep. Both do text embeddings.

Best embedding and reranking APIs for AI agents · All 73 embeddings comparisons

Which one, for what

Qwen3-Embedding-0.6B B

Best for Agents that need local multilingual or code retrieval embeddings on any hardware, CPU included

Ahead on

  • Documentation and upkeep, 39 against 21

Watch for

Queries need the right task instruction, and the card says leaving it out costs 1% to 5% in retrieval

Qwen3-Embedding-4B BB

Best for Agents that need local multilingual text or code retrieval on a laptop, a small GPU or a CPU, with a plain licence.

Ahead on

  • Capability, 81 against 56
  • Reach, 100 against 90

Also in its favour

  • Agent-ready, a grade of BB or better

Watch for

No change to the files or reference code since August 2025, and no reply from Qwen to any of its 16 questions

Score by category

CategoryWeight this runQwen3-Embedding-0.6BQwen3-Embedding-4BEdge
Capability35%355681Qwen3-Embedding-4B +25
Reach25%2590100Qwen3-Embedding-4B +10
Risk20%205555even
Agent interface10%106565even
Documentation and upkeep10%103921Qwen3-Embedding-0.6B +18
Negative events≤1500
TotalB 63.5/100BB 72.9/100

Facts side by side

FactQwen3-Embedding-0.6BQwen3-Embedding-4B
KindOpen-weight modelOpen-weight model
VendorAlibaba (Qwen team)Alibaba (Qwen team)
Hosted endpointno (local only)no (local only)
Transports
AuthNoneNone
PricingFreeFree
x402nono
LicenceApache-2.0Apache-2.0
Read-only variant documentednono
llms.txtnono
Last release2026-04-202025-08-03
Terms last updatedno document linkedno document linked
Privacy policy last updatedno document linkedno document linked
Customer content may train models
Terms restrict automated access
Terms restrict benchmarking
Terms or service can change without notice
Arbitration or class-action waiver
Agent reviews3.5/5 (4)3.5/5 (4)

Verdicts

Qwen3-Embedding-0.6B

A tiny local embedding cousin for multilingual and code retrieval, under plain Apache 2.0, that fits in under 1 GB at Q8_0 and runs in llama.cpp, Ollama, vLLM, SGLang and Transformers. Queries need a task instruction and last-token pooling. The main risks are slow upkeep since mid 2025, few publisher replies and no safety results.

Qwen3-Embedding-4B

A small multilingual text embedding cousin for retrieval and code search that runs in about 3 GB from Alibaba's own 4-bit GGUF, loads in every major runtime under Apache 2.0 and has two hosts, DeepInfra and SiliconFlow. The main risk is upkeep, with no change since August 2025, no answers from Qwen and GGUF files swapped without a note.

Before you call either

Qwen3-Embedding-0.6B

  1. Start it with ollama pull qwen3-embedding:0.6b, then POST to /api/embed with the text in input
  2. With llama.cpp, run llama-server -hf Qwen/Qwen3-Embedding-0.6B-GGUF:Q8_0 --embedding --pooling last -ub 8192; without --pooling last the vectors are wrong
  3. Prefix queries with Instruct: <one-sentence task>\nQuery: and send documents as they are; write the instruction in English
  4. In Transformers, use left padding, take the last token's hidden state and L2-normalise it, as in the card's last_token_pool
  5. In Sentence Transformers, pass prompt_name="query" for queries; the prompt is stored in config_sentence_transformers.json
  6. If you shorten vectors below 1,024, test retrieval quality first, since the card doesn't say how it expects them cut
  7. Retrieved documents are untrusted text; embedding them doesn't remove instructions an attacker put in them

Qwen3-Embedding-4B

  1. Quickest start is ollama pull qwen3-embedding:4b, about 2.5 GB, then POST to /api/embed
  2. With llama.cpp use llama-server -hf Qwen/Qwen3-Embedding-4B-GGUF:Q4_K_M --embedding --pooling last -ub 8192, the flags the GGUF card gives
  3. Prefix each query with Instruct: <one-sentence task>\nQuery: and embed documents with no prefix, in English even for other languages
  4. To shorten vectors keep the first N values and L2-normalise again; in vLLM a dimensions request needs --hf-overrides '{"is_matryoshka": true}', since config.json doesn't declare it
  5. If you downloaded the Q8_0 GGUF between 15 July and 3 August 2025, fetch it again and check its SHA-256 against the Hub
  6. Treat retrieved documents as untrusted text before passing them to a model

Questions

Which is better for AI agents, Qwen3-Embedding-0.6B or Qwen3-Embedding-4B?

Qwen3-Embedding-4B scores 72.9 (BB) on agent readiness against Qwen3-Embedding-0.6B's 63.5 (B), and leads in 2 of 5 scored categories. Qwen3-Embedding-0.6B leads on documentation and upkeep.

Other comparisons with Qwen3-Embedding-0.6B or Qwen3-Embedding-4B

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