FastChat vs MLC LLM
A side-by-side comparison of two self-hosted local llm runners options — licensing, setup difficulty, resource needs, and what each one replaces.
| Feature | FastChat | MLC LLM |
|---|---|---|
| Deploy effort | Under-an-hour setup | Read-the-docs project |
| Health score | 69 · Good | 95 · Excellent |
| Category | Local LLM Runners | Local LLM Runners |
| License | Apache-2.0 | Apache-2.0 |
| Language | Python | Python |
| Setup difficulty | Hard | Hard |
| Min. RAM | 8,192 MB | 4,096 MB |
| Deployment | docker, source | source, binary |
| GitHub stars | ★ 39,550 | ★ 23,185 |
| First released | 2023 | 2023 |
| Replaces | OpenAI API | OpenAI API |
What are FastChat and MLC LLM?
FastChat
FastChat is an open platform for training, serving, and evaluating large language model chatbots. It powers the Chatbot Arena and provides an OpenAI-compatible API server for self-hosted models.
- OpenAI-compatible API
- Web UI for model chat
- Distributed serving
- Model evaluation tools
MLC LLM
MLC LLM is a machine learning compiler and runtime that deploys language models natively across GPUs, CPUs, browsers, and mobile devices. It enables high-performance self-hosted inference on diverse hardware.
- Compile models for any hardware
- Native GPU acceleration
- Browser and mobile runtimes
- OpenAI-compatible serving
FastChat vs MLC LLM: key differences
Both projects are written in Python. MLC LLM is the lighter option, starting around 4,096 MB of RAM against 8,192 MB for FastChat. FastChat lists first-class Docker deployment; MLC LLM does not.
Why pick each one
Choose FastChat if…
- OpenAI-compatible API
- Powers Chatbot Arena
- Multi-model serving
Watch out for
- GPU recommended
- Steep learning curve
Choose MLC LLM if…
- Runs on diverse hardware
- Mobile and browser deployment
- Strong inference performance
Watch out for
- Models need compilation
- Complex toolchain setup
Frequently asked questions
Is FastChat or MLC LLM better?
Neither is universally better. FastChat has the larger community; both share a hard setup difficulty, so the decision comes down to features and licensing.
Are FastChat and MLC LLM free and open-source?
Yes. FastChat is licensed under Apache-2.0 and MLC LLM under Apache-2.0. Both can be self-hosted at no software cost.
Can I run FastChat and MLC LLM with Docker?
FastChat: yes. MLC LLM: check the project docs for container support.
Which is lighter on resources, FastChat or MLC LLM?
MLC LLM has the smaller minimum footprint at 4,096 MB of RAM, compared to about 8,192 MB for FastChat. Real-world usage depends on library size, user count, and enabled features.