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Qwen3.5-4B is an open-weights model from Qwen, with 4.66 billion parameters and no API price: the cost depends on where you run it. The declared license is apache-2.0.
Each tick is an open model in the catalog; the black tick is the median. Logarithmic scale: each axis mark is ten times the previous one. Downloads in the last 30 days, from the Hugging Face API.
Price
Open-weights model, with no API price from the company: the cost depends on where you run it (your own server or a cloud provider).1
All 12 from QwenCompare with other modelsFull pricing table
Quality on tests
Qwen3.5-4B does not appear on the LMArena text leaderboard published on Oct 8, 2026, or it appears under a name that CertuAI could not match to this model with certainty.4
In Portuguese: the repository Qwen/Qwen3.5-4B was not evaluated on the Open Portuguese LLM Leaderboard, which is archived and no longer accepts new models (last evaluation on Sep 1, 2025).5
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Qwen3.5-4B is an open-weights model: anyone can download and run it, so there is no single price. What it costs depends on where you run it (on your own server or with a cloud provider, each with its own price list). Qwen publishes API pricing on its own page, but it is not included here because Alibaba Cloud's terms prohibit collecting content with bots without written permission: price not published on a page open to automated reading.
Source:Hugging Face, public models API, accessed Oct 13, 2026. What the number measures: Data from the company's official repository on Hugging Face: the license declared on the model card, the total parameter count of the safetensors files (when the repository publishes it), downloads in the last 30 days and all time, likes, the main task, whether downloading requires accepting terms first, and the position limit from config.json (max_position_embeddings, a technical cap that is not the advertised context window). How the name was matched: Text-generation repositories from each company's official organizations are included: the 6 most downloaded in 30 days and the 6 with the most likes, excluding quantized versions, Base models, safety models or test models, with at least 1,000 downloads in 30 days. A repository with the same name as a model on the same company's pricing page counts as a single model.
What it reads: inferred from the main task declared in the official Hugging Face repository (image-text-to-text). A field the official source does not provide is left out of the fact sheet and shows up in the “Not stated in the official source” line.
Source:LMArena, text leaderboard, public dataset on Hugging Face (CC BY 4.0 license), published Oct 8, 2026, accessed Oct 13, 2026. What the number measures: Score on the LMArena text leaderboard, in the style-controlled version and the overall category: people send the same question to two models without knowing which ones they are and vote for the better answer, and LMArena turns the votes into a score. The higher it is, the more often the model won. The confidence range is the interval LMArena itself publishes for the score. The rank is the position on the full leaderboard, which includes models outside this catalog. How the name was matched: Same company and same name, ignoring dots, spaces and hyphens. It also accepts the name with the reasoning level at the end (high, medium, low, minimal) and the name with a date at the end when LMArena only knows that model by a date.
Source:Open Portuguese LLM Leaderboard (open leaderboard of Portuguese-language models) (Apache 2.0 license), accessed Oct 13, 2026. What the number measures: Average, from 0 to 100, of nine tests in Portuguese: ENEM, the USP and Unicamp university entrance exams (BLUEX), the OAB bar exam, sentence understanding (ASSIN2 RTE and STS, FaQuAD NLI), hate speech (HateBR and Portuguese Hate Speech) and sentiment in tweets (TweetSentBR). The leaderboard only evaluates open-weights models, running the weights at the stated precision, and it is archived (it no longer receives new models). How the name was matched: The repository evaluated on Hugging Face is the same official company repository the catalog uses for the model. The normalized average (NPM) subtracts what a random guess would get right on each test.
In short
Qwen3.5-4B, from Qwen, is an open-weights model with no API price from the company. See license, size, downloads and test scores, with source and date.
About CertuAI: CertuAI is the AI that answers a small business's WhatsApp, Instagram and Messenger 24/7, with a built-in CRM, and is a Tech Provider on Meta's WhatsApp Business Platform. Paid plans start at US$ 75 a month, with no lock-in. Create my agent