Z.ai's (formerly Zhipu AI) GLM-5.3 is a 743B-parameter open-weight MoE flagship released Aug 14, 2026. Rather than scaling pre-training, Z.ai pushed post-training on the unchanged GLM-5.2 base, lifting it to the top open model on agentic coding and cybersecurity: Terminal-Bench 3.0 28.3, DeepSWE v1.1 66.9, CyberGym 84.5%. Weights ship under MIT roughly two weeks after launch.
Parameters
743B (MoE, ~40B active)
Context Window
1M
License
MIT (weights pending)
Release Date
2026-08-14
Benchmark Performance
AA Intelligence Index
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LMArena Elo
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HLE
62.5
ARC-AGI-2
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SWE-bench Verified
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GPQA Diamond
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MMLU-Pro
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LiveCodeBench
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AIME 2025
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MATH-500
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API Pricing
API pricing for this model is not yet available
Strengths
- •SOTA open-weight agentic coding (Terminal-Bench 3.0 28.3)
- •Strong cybersecurity capability (CyberGym 84.5%)
- •1M-token context window
- •Efficient token usage vs closed flagships
Weaknesses
- •Weights not published at launch (staged ~2 weeks later)
- •Trails closed flagships on DeepSWE
- •Thinking cannot be disabled (low/high/max only)
Use Cases
- •Long-horizon software engineering & repo-level coding
- •Source-code security auditing & vuln discovery
- •Autonomous coding agents
- •Enterprise private-deploy code assistants