What is Vicuna?
Vicuna is an open-source chatbot project from the LMSYS Org research group, presented on the LMSYS homepage as an open-source chatbot that impresses GPT-4 with 90%* ChatGPT quality. It belongs to the LMSYS family of projects, which also includes SGLang, FastChat, Chatbot Arena and RouteLLM.
The homepage text does not describe Vicuna's interface, training details or how to run it in any detail, so the exact workflow is not stated there. What the page does establish is that Vicuna is one of the chatbot models LMSYS releases openly, and that the wider organization provides the tooling around such models, such as the FastChat platform for training, finetuning, serving and evaluating chatbots.
Key features
- Open-source chatbot model
- Reported about 90% of ChatGPT quality (per the homepage)
- Part of the LMSYS ecosystem with FastChat for serving and evaluation
Who is it for
- Researchers working on open LLMs
- Developers building chatbots
- Teams wanting self-hosted chat models
Pros and cons
- Open source
- Strong quality claim relative to ChatGPT, per the homepage
- Homepage gives no pricing or hosting details
- The 90% figure is marked with an asterisk and its basis is not explained on the page
Vicuna pricing
The vendor does not publish prices in a readable form (often pricing is shown only after signing in).
Is Vicuna free?
The vendor does not state this clearly on the homepage or pricing page.
Vicuna alternatives
| Tool | Price from | Free plan | Category |
|---|---|---|---|
 Grok | 30 USD/mo | yes | Chatbots & AI assistants |
 DeepSeek | 0.02 USD | ? | Chatbots & AI assistants |
 HuggingChat | not listed | ? | Chatbots & AI assistants |
 Open WebUI | not listed | yes | Chatbots & AI assistants |
 Arena AI | not listed | ? | Chatbots & AI assistants |
 ChatGPT | 34,99 PLN/mo | yes | Chatbots & AI assistants |
FAQ
What is Vicuna used for?
Open-source chatbot fine-tuned from LLaMA, reaching about 90% of ChatGPT quality, for researchers and developers.
Is Vicuna free?
The vendor does not state this clearly on the homepage or pricing page.
How much does Vicuna cost?
The vendor does not publish prices publicly or requires sign-in.
What are the best Vicuna alternatives?
Closest alternatives: Grok, DeepSeek, HuggingChat, Open WebUI, Arena AI.
Data checked October 12, 2026 on the vendor website (lmsys.org).