Three days. That’s how long it took Z.AI’s newest model to climb near the top of one of the most competitive AI coding benchmarks around. GLM-5.2 (Max) hit the #2 spot on Arena.ai’s Code Arena: Frontend leaderboard by June 16, scoring between 1,593 and 1,595 points, trailing only Fable 5.
For context, it beat Claude Opus 4.7 (Thinking) by 29 points.
What GLM-5.2 actually is
Z.AI, the Chinese AI company formerly known as Zhipu AI, released GLM-5.2 (Max) around June 13. The model uses a Mixture-of-Experts (MoE) architecture, which is essentially a way of building very large models that only activate a fraction of their total capacity for any given task.
The total parameter count lands somewhere between 744B and 753B, but only about 40B parameters are active at any given time. That keeps inference costs manageable while still tapping into a massive knowledge base.
