GLM (Z.ai)

GLM is developed by Zhipu AI, which markets its models and products internationally under the Z.ai brand at z.ai. Zhipu AI was founded in 2019 as a spin-off from the Knowledge Engineering Group at Tsinghua University and is headquartered in Beijing. It has raised substantial capital from investors including Alibaba, Tencent, Meituan, Ant Group, Xiaomi, HongShan, and Prosperity7 Ventures, and it became the first publicly listed large language model company through a Hong Kong IPO (HKEX: 2513).

The company builds the GLM (General Language Model) family alongside multimodal models and agent systems, and it has pursued an open-weight strategy that publishes model weights under permissive licenses. This positions Z.ai as both a commercial API provider and a major contributor to the open-source AI ecosystem.

The GLM-5.x series is a large Mixture-of-Experts architecture (the GLM-5.2 flagship is around 744B total parameters with roughly 40B active per token) built for agentic coding, tool use, and long-context reasoning, with very large context windows on the flagship releases. Weights for major releases such as GLM-5.2 are openly available on Hugging Face (zai-org) and ModelScope under the MIT license, enabling self-hosting, fine-tuning, and commercial deployment.

Beyond raw models, Z.ai delivers GLM through several channels: a free chat interface at chat.z.ai, an OpenAI-compatible API with competitive per-token pricing and free Flash tiers, and a GLM Coding Plan that integrates the models into agentic coding tools like Claude Code, Cline, and OpenCode. This combination lets teams choose between hosted convenience and full self-managed control.

GLM primarily targets developers, engineering teams, and AI researchers who want a high-performing open-weight model for coding assistants, autonomous agents, and long-context applications, especially those seeking self-hosting, fine-tuning, or lower API costs than closed frontier providers. It also serves cost-sensitive startups and enterprises evaluating open-source alternatives, as well as individual users who simply want free access to a capable chatbot at chat.z.ai.

Zhipu AI (Z.ai) has raised substantial funding, including a roughly RMB 2.5B round in 2023 backed by Alibaba, Tencent, Meituan, Ant Group, Xiaomi, and HongShan, and a ~$400M round in 2024 led by Prosperity7 Ventures, plus later state-linked investment. It became the first publicly listed LLM company via a Hong Kong IPO (HKEX: 2513) in early 2026.