LMSYSORG

The Large Model Systems Organization develops large models and systems that are open, accessible, and scalable.

15+Projects
75K+GitHub Stars
1000+Contributors

Latest Blog

See all posts
News

Announcing the Recipient of the 2026 LMSYS PhD Fellowship

We are delighted to announce the first recipient of the LMSYS Fellowship Program: Will Lin. Following the launch of our Fellowship Program and careful review of applications, we selected Will for his...

June 08, 2026
Blog

No Token Left Behind: Demystifying Token-In-Token-Out in Miles

In agentic RL, a rollout is not a single generation. It is a chain of model calls, tool outputs, harness messages, and resumed generations. Token-In-Token-Out (TITO) is a design principle that address...

June 5, 2026
Blog

Higgs Audio v3 TTS on SGLang-Omni: Real-Time, Controllable Speech for Voice Agents

Today we are announcing end-to-end serving for Higgs Audio v3 TTS on SGLang-Omni. Higgs Audio v3 TTS is Boson AI's text-to-speech model for conversational voice agents: it generates natural and expres...

June 4, 2026

Projects

View all projects
SGLang
SGLangstars

A fast serving engine for LLMs and VLMs.

SGLang
Chatbot Arena
Chatbot Arena
Chatbot ArenaGraduated

A benchmark platform for LLMs that features anonymous, randomized battles in a crowdsourced manner.

FastChat
FastChatstars

An open and scalable platform for training, finetuning, serving, and evaluating LLM-based chatbots.

FastChat
Vicuna
Vicuna
Vicuna

An open-source chatbot impressing GPT-4 with 90%* ChatGPT quality.

RouteLLM
RouteLLMstars

A framework for serving and evaluating LLM routers.

RouteLLM

Our Sponsors & Partners

Backed by leading companies and institutions advancing AI research.

Voltage Park, NVIDIA, Nebius, Google Cloud, AtlasCloud, a16z, AMD, InnoMatrix, Laude Institute, Hyperbolic, NovitaAI, Verda Cloud, Sky9, Kaggle, MBZUAI, Together, RunPod, Anyscale, HuggingFace