Z.ai develops open-source large language models (GLM-4.5 and GLM-4.5-Air) that aim to unify reasoning and non-reasoning capabilities in a single architecture. GLM-4.5 uses a Mixture of Experts design with 355 billion parameters (about 32 billion active at a time) and scored third globally across 12 industry tests, with a 90.6% tool-calling success rate and 98.2% on the MATH500 benchmark. The company released model weights under an MIT license on Hugging Face and GitHub and prices API calls at $0.11 per million input tokens and $0.28 per million output tokens—roughly one-fifth the cost of comparable Western models. Its models include a hybrid reasoning setup with a "thinking" mode for complex planning and a fast "non-thinking" mode for instant responses, and Z.ai has published demos showing website generation and interactive visualizations. To build an ecosystem, Z.ai launched a 1.5 billion yuan ($211M) "Z Fund" to invest in startups using its technology. The company, spun out from Tsinghua University in 2019, is preparing a Hong Kong IPO to raise about $300M and continues operations despite being added to the U.S. Entity List.

Total raised

$1.5B

Funding rounds

1

Latest round

Equity

Latest activity

Jul 2025