Qwen3.5 4B is a language model from Qwen. It ranks #152 of 350 on ModelCap's current board, with an Index score of 41.0, modeled from the publisher's launch results against measured models. Its score range of 26.1–55.8 spans positions #93–#254. Its weights are openly downloadable.
OpenRouter endpoint status could not be refreshed. This model is not treated as currently served until a successful observation arrives.
Input
Self-hosted
weights only · no listed API price
Output
Self-hosted
weights only · no listed API price
Context
—
tokens
Providers
0
endpoints
Providers
Uptime measured over the last 30 minutes
Current provider status is unavailable.
Reported evaluation leads (15)
Not independent measurement
Structured rows reported in this exact model repository at the pinned revision below. They are the publisher talking about itself: never measured evidence, never a score input on their own. Rows marked as used were laddered against independently measured peers inside the launch-card channel of this model's modeled placement, with the replay-measured optimism haircut applied; the others played no part.
Modeled from the publisher's launch results against measured models
Current board
#152 of 350
Score range
26.1–55.8
Rank range
#93–#254
Technical details
Public rank basis
Modeled · peer benchmarks (architecture)
Evidence label
Modeled · peer benchmarks · publisher-corpus-prior over 211 held-out anchors (25%); launch card against 3 resolved peers on 10 rows (75%); exceeds every named peer on 2 of 10 rows; optimism haircut 0.6 from cross-lab-probe; shrunk 2.9 up toward the measured corpus
How this position was produced · fused launch placement
No general-family board lists this model yet. Its point estimate is the precision-weighted mean of every channel that spoke for it; each channel’s share is the weight it carried. Independent measurements replace this placement as boards list the model.
Fused estimate
41.0 ± 11.6
Independent share
0%
Shrink toward corpus
+2.9
Peer ceiling share
20%
Optimism haircut
−0.6 points · cross lab probe, 2 probes
Method
precision-weighted-v1
Channels fused into this model’s launch placement
Channel
Estimate
Share
Publisher corpus prior · not independent
publisher-corpus-prior over 211 held-out anchors
49.7 ± 23.3
25%
Launch card against resolved peers · not independent
launch card against 3 resolved peers on 10 rows
38.1 ± 13.4
75%
· Launch card row aa-lcr: claims above every resolved peer
· Launch card row gpqa-diamond: inside the resolved peer range
· Launch card row hmmt-feb-25: inside the resolved peer range
· Launch card row hmmt-nov-25: claims below every resolved peer
· Launch card row ifbench: claims below every resolved peer
· Launch card row ifeval: claims above every resolved peer
· Launch card row livecodebench-v-6: claims below every resolved peer
· Launch card row mmlu-pro: inside the resolved peer range
· Launch card row mmlu-prox: inside the resolved peer range
· Launch card row mmlu-redux: inside the resolved peer range
Bayesian Evidence Score · measured evidence input only
BES normalizes admitted public benchmark evidence for measured Index rows. Its legacy score and observables prior do not define the public language rank.
Observed capability
—
Evidence status
No admitted measured evidence
General preference
—
Coding
—
Agents & tools
—
Reasoning
—
Evidence breadth
0%
Evidence coverage
0%
Market and catalogue signals · secondary, never the language Index rank
Usage (OpenRouter popularity)
—
Liquidity (providers × uptime)
—
Open reach (HF downloads)
99.7
Surface (context / tools / modalities)
15.0
Freshness
40.2
· HF 30d downloads 7513368
· Catalogue: modalities Text/Image
· First seen 2026-02-27
These adoption and deployment observations remain context only. They do not change this model's ModelCap Index score or rank.
The bounded 0–100 capability score blends each source’s competitive placement with its published achievement, then combines capability families. Evidence breadth adds a modest uncertainty adjustment; price and popularity are not part of benchmark-led rank.
Not yet published: a current serving provider, measured provider uptime, published provider pricing, declared context and output limits, admitted benchmark results, results across several capability areas, results from more than one source, a confident match to its benchmark entries, pinned evaluation dataset versions.
A metadata completeness and deployability index—not a safety certification, quality grade, or production-readiness claim.
Market Gravity uses OpenRouter’s full-catalogue popularity order. Sparse Vercel top-ten observations appear only when published and do not affect the score.
Arena preference
No matched Arena rating
This model is visible because it is available in the live catalogue, but it has no trustworthy community result yet. ModelCap does not infer a quality score from price, features, or market activity.
Market Gravity breakdown
Usage55%
0.0
OpenRouter weekly popularity across the full model catalogue.
Liquidity25%
0.0
Independent providers versus the model's open or closed cohort, weighted by uptime.
Open reach15%
99.7
Hugging Face 30-day downloads for open models; neutral for closed models.
Freshness5%
40.2
Time since first public availability, on a six-month half-life.
Specification
Model ID
Qwen/Qwen3.5-4B
Declared output cap
Unknown
OpenRouter catalogue or provider-endpoint declaration. Limits can vary by provider and prompt length; a model-wide maximum has not been independently verified. OpenRouter metadata
Inputs
Text, Image
Outputs
Text
Cached input tokens
Not offered
First seen on OpenRouter
27 Feb 2026
Capabilities
Not supported: Reasoning
Not supported: Tool use
Not supported: Structured output
Not supported: Response format
Not supported: Moderated
Weights & access
Open weights. Downloadable weights are published under an OSI or free-culture license in the current repository metadata. This describes weight availability, not whether the full training stack qualifies as Open Source AI.
Qwen3.5 4B holds ModelCap Index position #152 of 350 ranked language models as of 24 October 2026, with an Index score of 41.0 (interval 26.1–55.8); evidence: modeled · peer benchmarks. The Index combines public benchmark boards with published uncertainty; the methodology page explains the weighting.
How much does Qwen3.5 4B cost per 1M tokens?
No live API price is listed for Qwen3.5 4B in the current snapshot as of 24 October 2026 because the latest endpoint refresh was unavailable. ModelCap shows a price only when a provider currently lists one.
Is Qwen3.5 4B open-weight?
Open weights (apache-2.0). Downloadable weights are published under an OSI or free-culture license in the current repository metadata. This describes weight availability, not whether the full training stack qualifies as Open Source AI. The repository is Qwen/Qwen3.5-4B on Hugging Face.
Which benchmarks has Qwen3.5 4B been evaluated on?
Qwen3.5 4B has published results on 3 public boards tracked by ModelCap as of 24 October 2026: AA Terminal-Bench 2.1 25.8% (#80 of 124), AA τ²-Bench Telecom 92.1% (#11 of 152) and AA Humanity's Last Exam 9.9% (#157 of 265). Each board page ranks every tracked model on that benchmark. The ModelCap Index scores the results its methodology admits, with published uncertainty, and shows reference boards without scoring them.
How does Qwen3.5 4B compare with Qwen3.5 2B?
Qwen3.5 4B ranks #152 (Index 41.0) and Qwen3.5 2B ranks #153 (Index 40.8) on the ModelCap Index as of 24 October 2026. The head-to-head page lines up their benchmarks, listed prices, context windows and provider counts side by side.
When was Qwen3.5 4B released?
Qwen3.5 4B first appeared in the catalogue on 27 Feb 2026. It is the current version in its family. Rank and price movements since then are recorded on the site's changes feed.