Z.ai Releases GLM-5.3 Weights With 756GB Package and Revenue-Based License Tier

Z.ai released the open weights for its GLM-5.3 model on Friday, distributing 756GB of files across 141 Safetensors shards with support for vLLM and SGLang. The model shares the same base architecture as GLM-5.2, with performance gains driven entirely by post-training techniques including reinforcement learning and domain-specific data for software engineering and vulnerability research. Benchmark scores improved significantly on Terminal-Bench, DeepSWE, and ExploitBench, though these were vendor-run evaluations and independent results may vary. The accompanying license allows free use for individuals, startups, and internal enterprise deployments, but requires a Z.ai security review for cloud platforms with group revenues exceeding ten billion dollars before they can offer GLM-5.3 inference or fine-tuning APIs. For developers not running their own infrastructure, Cloudflare has already added GLM-5.3 to its Workers AI platform at launch, priced at $1.40 per million input tokens and $4.40 per million output tokens.