Qwen3-Reranker
The Qwen3-Reranker family (0.6B / 4B / 8B) are Apache 2.0 rerankers built on Qwen3, with a 32K context, 100+ languages and support for a task instruction. In Qwen’s own tests the 4B and 8B lead bge-reranker-v2-m3 and gte-multilingual-reranker on every suite they ran — English, Chinese, multilingual, long-document and code. Those are Qwen’s numbers on Qwen’s setup: validate on your own labels before replacing bge or a hosted API.
Model variants
| Model | Parameters | Layers | Best for |
|---|---|---|---|
Qwen/Qwen3-Reranker-0.6B | 0.6B | 28 | Lightest; still prefers a GPU |
Qwen/Qwen3-Reranker-4B | 4B | 36 | Default self-host pick — best English and instruction-following scores of the three |
Qwen/Qwen3-Reranker-8B | 8B | 36 | Leads on Chinese, multilingual, long-document and code — by at most 1.5 points |
All three: 32K context, 100+ languages, Apache 2.0.
For images, screenshots and video there is a separate family, Qwen3-VL-Reranker (2B / 8B, 32K context, 30+ languages, Apache 2.0). In Qwen’s own runs on ViDoRe v3, a visual-document retrieval benchmark, the 8B scores 66.7* and the 2B 60.8*; it is in the models table alongside LightOn-rerank, which also scores page images.
Recommendation: start with 4B on a single modern GPU. Drop to 0.6B only if memory is tight; move to 8B only when labelled eval shows a clear NDCG gain worth the cost.
Scores, and whose they are
| Model | MTEB-R | CMTEB-R | MMTEB-R | MLDR | MTEB-Code | FollowIR |
|---|---|---|---|---|---|---|
| bge-reranker-v2-m3 | 57.03 | 72.16 | 58.36 | 59.51 | 41.38 | -0.01 |
| Qwen3-Reranker-0.6B | 65.80* | 71.31 | 66.36 | 67.28 | 73.42 | 5.41 |
| Qwen3-Reranker-4B | 69.76* | 75.94 | 72.74 | 69.97 | 81.20 | 14.84 |
| Qwen3-Reranker-8B | 69.02* | 77.45 | 72.94 | 70.19 | 81.22 | 8.05 |
Qwen’s own runs, from the model cards: the retrieval subsets of MTEB (English v2, Chinese v1, multilingual MMTEB and Code), MLDR for long documents and FollowIR for instruction-following, each reranking the top 100 candidates from Qwen3-Embedding-0.6B. MTEB-R is an English NDCG@10 average, but it isn’t the BEIR suite, so these numbers don’t share a column with other vendors’ BEIR figures.
One outside reference: Jina’s 2026 run puts Qwen3-Reranker-4B at 62.28* on 13 BEIR datasets — just under jina-reranker-v3.5 there, and ahead of it on multilingual, legal / medical and structured retrieval (see the Jina page). Until October 2026 this page compared Qwen’s scores with “bge (~60)” and “mxbai (~62)”; neither figure had a source, and the models table now shows what BAAI and mixedbread actually publish.
Quick start
sentence-transformers
pip install sentence-transformers
from sentence_transformers import CrossEncoder
model = CrossEncoder("Qwen/Qwen3-Reranker-4B")
# Default instruction: "Given a web search query, retrieve relevant
# passages that answer the query" — override it per task:
model = CrossEncoder(
"Qwen/Qwen3-Reranker-4B",
prompts={"support": "Prefer official help articles with step-by-step instructions"},
default_prompt_name="support",
)
ranked = model.rank(query, documents) # [{"corpus_id": i, "score": s}, ...]
The model cards load the rerankers straight into sentence-transformers’ CrossEncoder. The card also shows a plain transformers path (transformers ≥ 4.51) that scores yes/no logits through Qwen’s chat template — get that template wrong and quality drops without an error.
In a RAG pipeline
# Pseudocode — same two-stage pattern as any cross-encoder
candidates = vector_db.search(query, top_k=80) # or hybrid
scores = qwen3_rerank(query, candidates) # official template
top = sorted(zip(scores, candidates), reverse=True)[:8]
answer = llm.complete(context=top, query=query)
When to pick Qwen3
- Yes: you have GPU, need multilingual quality, and want open weights without per-call API cost.
- Yes: long passages matter — all three take 32K tokens.
- Yes: relevance needs steering. The rerankers take a task instruction; Qwen recommend writing one per task (in English, even for multilingual data) and report typical gains of 1–5%. See instruction-following rerank.
- Maybe not: CPU-only or edge — prefer bge-v2-m3, mxbai, or Jina tiny for demos.
Pros and cons
Pros
- Apache 2.0 at every size, 0.6B to 8B
- 100+ languages and a 32K context
- Takes a task instruction — the 4B has the best FollowIR score in Qwen’s table
- Loads directly with sentence-transformers’
CrossEncoder - Zero per-call cost once self-hosted
Cons
- GPU (or heavy quant) required for comfort
- The raw
transformerspath needs Qwen’s exact prompt template - Vendor numbers are MTEB-R, not BEIR
- Too large for our in-browser demo
Compare on your data first
Use a tiny browser model to learn the UX of reranking, then A/B Qwen3-4B vs bge-v2-m3 on 30 labelled queries.
Open the demo → Evaluate guide →