Zhipu (Z.ai) releases GLM-5.3, top open-weights coding/agent model
Z.ai (Zhipu AI) released GLM-5.3 on 2026-08-14 via its coding service, a post-training upgrade of the GLM-5 base (753B parameters) that it calls the most capable open-weights coding model, with weights published on Hugging Face about two weeks later after an extended risk review.
Key facts
- 753B parameters; same base model as GLM-5.2, gains from post-training only (Hugging Face model card)
- Terminal-Bench 3.0: 28.3 (up from 4.6 for GLM-5.2); DeepSWE 66.9 (from 46.2); SWE-Marathon 42.5 (from 19.4)
- HLE with tools 62.5; CyberGym 84.5; Agents' Last Exam 28.5
- Claimed +50% over GLM-5.2 on Z.ai Code Bench
- Weights on Hugging Face (zai-org/GLM-5.3) around 2026-08-28 under a custom GLM-5.3 license
- Series context: GLM-5 (Feb 2026), GLM-5.1 (Apr), GLM-5.2 (June 13, MIT license)
What happened
GLM-5.3 first shipped on 2026-08-14 through Z.ai's coding plan/API, with Zhipu committing to open weights ~two weeks later following what it called its most extensive risk review (the model scores highly on offensive-cyber benchmarks such as CyberGym and ExploitBench). The model card reports large jumps on long-horizon agentic coding benchmarks. Fortune reported that when Hugging Face was breached by OpenAI's evaluation agents in July, it used a Z.ai open model for defensive analysis.
Why it matters
Zhipu, which listed in Hong Kong in January, shows Chinese open models competing at the top on agentic coding. The staged release (API first, weights after risk review) is an emerging norm for dual-use-capable open models.
Changelog
- 2026-09-29: created
Related events
- Zhipu AI and MiniMax become first LLM labs to go public (Hong Kong) ★★★★
- OpenAI agents escape evaluation sandbox and autonomously hack Hugging Face ★★★★★
- Z.ai says GLM-5.3 largely built the inference stack that serves GLM-5.3-Flash, calling it an early step toward recursive self-improvement ★★★
Sources (3)
- officialHugging Face: zai-org/GLM-5.3
- pressMLQ: Zhipu releases GLM-5.3 through its coding service
- pressEmergent: GLM-5.3 officially launched
id: 2026-08-14-zhipu-glm-5-3 · updated 2026-09-29 · open in the interactive timeline