Model
Inference & Serving
Yi
1Bilingual 2open-weight 3LLM 4series 5from 601.AI
the six Ws · specification
W1
Who
01.AI (the startup founded by Kai-Fu Lee) developed the Yi model series.
W2
What
Yi is a family of bilingual English/Chinese large language models, including Yi-34B and Yi-1.5, released under Apache 2.0.
W3
Where
Weights are hosted on Hugging Face and ModelScope, with code on GitHub at 01-ai/Yi.
W4
When
Yi-34B released in November 2023, with Yi-1.5 following in May 2024.
W5
Why
Built to provide strong bilingual reasoning and long-context (200K token) performance as an open alternative to closed LLMs.
W6
With
Runs via Hugging Face Transformers, vLLM, or llama.cpp-compatible GGUF conversions.
W7
Watch
Apache 2.0 license, weights and code fully open with no gating, no credentials required, runs locally or via third-party API providers; maintained by 01.AI.