What is Qwen1.5 72B?
Qwen1.5 72B is a 72-billion-parameter open large language model from Alibaba Cloud, part of the widely adopted Qwen (Tongyi Qianwen) family. It is a strongly multilingual model — excellent in both Chinese and English, plus many other languages — with competitive reasoning, coding and chat ability and a 32K-token context. The Qwen1.5 series spans a wide range of sizes (from 0.5B up to 72B), all with base and chat-tuned variants, and brought broad ecosystem support that made the family a popular open choice worldwide.
The model family
Qwen1.5 models are decoder-only transformers trained on a large, multilingual corpus with a strong emphasis on Chinese and English alongside code and maths. The 72B is the flagship of the 1.5 generation, offering the strongest quality, while smaller sizes serve lighter needs. All come in base and Chat variants, support a 32K context, and integrate smoothly with the popular open-source serving and fine-tuning ecosystem, which helped drive rapid adoption.
What it is good at
Qwen1.5 72B is a strong general-purpose, multilingual model: chat and assistants, reasoning, summarisation, coding and especially tasks involving Chinese or mixed Chinese-English content, where it is a leading open option. It suits multilingual applications, region-specific assistants, RAG and fine-tuning, and its long context handles substantial documents. The Chat variant provides assistant behaviour directly, and the family's size range lets you match capability to hardware.
Licensing & access
Qwen1.5 weights are released openly on Hugging Face under Qwen's licence terms (the Tongyi Qianwen licence, which permits commercial use within its conditions — review them for your case; many smaller Qwen sizes are Apache 2.0). It runs via Transformers, Ollama and most serving frameworks, and is also offered through Alibaba's cloud API. The 72B needs substantial multi-GPU memory or quantisation; smaller Qwen1.5 sizes are far more accessible.
Practical considerations
Use the Chat variant for assistants and the base for fine-tuning. At 72B you need real GPU resources, so budget multi-GPU or quantised deployment, or use a smaller Qwen1.5 size for lighter hardware. Check the specific licence of the size you deploy. Note that Alibaba has since released newer Qwen generations (Qwen2, Qwen2.5 and beyond) that improve on 1.5 — compare them when you need the latest quality, though Qwen1.5 72B remains strong and well-supported.
How it compares
Against Yi-34B (another strong bilingual model), Llama 2 and Mixtral, Qwen1.5 72B's strengths are its excellent multilingual ability — especially Chinese — broad size range and 32K context. It often leads open models on Chinese tasks and is competitive in English. For applications centred on Chinese or genuinely multilingual use, Qwen is among the best open choices; for English-only frontier quality, newer or different models may compete closely.
Getting started
Pull Qwen1.5 (start with a smaller Chat size to prototype, or 72B-Chat for top quality) from Hugging Face or Ollama, or use Alibaba's API, and prompt it in any supported language. Use the Chat variant for assistants and the base for fine-tuning, run quantised builds to fit your GPUs, and and seriously consider the newer Qwen2 and Qwen2.5 releases whenever you want the latest quality improvements over this 1.5 generation.
