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FastChat vs. Qwen

LLM Comparison


FastChat

FastChat

Overview

FastChat is the open platform for training, serving, and evaluating LLM chatbots developed and maintained by LMSYS.


FastChat is an open-source library for training, serving, and evaluating LLM chat systems from LMSYS. It includes training and evaluation code, a model serving system, a Web GUI, and a finetuning pipeline, and is the de facto system for Vicuna as well as FastChat-T5. FastChat also includes the Chatbot Arena for benchmarking LLMs.


Initial release: 2023-04-28

Qwen

Overview

Qwen is Alibaba's broad family of open and hosted models for reasoning, coding, multimodal understanding, and agents. Qwen 3.8 Max Preview is the current generation.


Qwen, formerly Tongyi Qianwen, is a family of language and multimodal models developed by Alibaba. It includes general-purpose, coding, vision-language, audio, embedding, and reasoning variants. Qwen 3.8 Max Preview is the current hosted flagship, with support for multimodal and agentic workflows. Earlier Qwen generations, including Qwen 3.6 checkpoints, remain available as Apache 2.0 open weights; availability and licensing should therefore be checked per model.


Initial release: 2023-09-13

Current generation: Qwen 3.8

Reference

https://qwen.ai/

FastChat

Qwen

Products & Features
Instruct Models
Coding Capability
Customization
Finetuning
Open Source
License Apache 2.0 Mixed; Apache 2.0 open weights and hosted previews
Model Sizes 3B Undisclosed for Qwen 3.8 preview