Microsoft makes powerful Phi-4 model fully open-source on Hugging Face

Even as its big investment partner OpenAI continues to announce more powerful reasoning models such as the latest o3 series, Microsoft is not sitting idly by. Instead, it’s pursuing the development of more powerful small models released under its own brand name.

As announced by several current and former Microsoft researchers and AI scientists today on X, Microsoft is releasing its Phi-4 model as a fully open-source project with downloadable weights on Hugging Face, the AI code-sharing community.

“We have been completely amazed by the response to [the] phi-4 release,” wrote Microsoft AI principal research engineer Shital Shah on X. “A lot of folks had been asking us for weight release. [A f]ew even uploaded bootlegged phi-4 weights on HuggingFace…Well, wait no more. We are releasing today [the] official phi-4 model on HuggingFace! With MIT licence (sic)!!”

Weights refer to the numerical values that specify how an ...