Z.ai Drops GLM-5.2, a 753B Open-Weights Monster With 1M Token Context

Chinese AI lab Z.ai has released GLM-5.2, an open-weights model that's hard to ignore on paper: 753 billion parameters, a Mixture-of-Experts architecture, and a 1 million token context window. That context length puts it in the same conversation as Gemini's long-context lineup, and the open-weights release means developers can actually run it rather than just rent access.

Z.ai hasn't been a household name in Western AI circles, but GLM-5.2 lands during a week when the broader market is already digesting DeepSeek's preview of a 1.6 trillion parameter V4 model — so competition at the high end of open-source is clearly heating up fast.

No independent benchmark results have been published yet, so the real-world performance story is still wide open. I'd treat any capability claims cautiously until third-party evals come in. What's already notable, though, is that a fully open 750B-class model with million-token context exists at all — that was a closed-lab luxury not long ago.

Model weights and API details are available via Z.ai's official channels.