GLM-5.3
Overview
GLM-5.3 is a text foundation model released by Z.AI on August 14, 2026 for complex coding, long-horizon agent tasks, and cybersecurity work. It uses the same base model as GLM-5.2; Z.AI attributes the update's gains to scaled post-training across more environments, more diverse tasks, and longer trajectories.
GLM-5.3
Eligibility: This offer applies to GLM-5.3 requests made through the B.AI API and B.AI web app.
For a limited time, eligible requests are billed at 90% of the standard reference price. The promotional prices per 1 million tokens are: Input $1.26, Cache Write $1.26, Cache Read $0.252, and Output $3.96.
This page continues to show standard reference prices. Offer end time, eligibility, actual settlement prices, and final billing are subject to the platform display.
Key Features
- Scaled Post-Training: Retains the GLM-5.2 base model while expanding reinforcement-learning environments, task diversity, and training compute for long-horizon professional workflows.
- Configurable Always-On Reasoning: Supports
low,high, andmaxreasoning effort, withmaxas the default. Native GLM-5.3 requests require thinking to remain enabled. - Coding and Agent Performance: Z.AI reports 28.3 on Terminal-Bench 3.0, 66.9 on DeepSWE v1.1, 78.1 on FrontierSWE, and 48.2 on AutomationBench v1.0.6.
- Cybersecurity Evaluation: Z.AI reports 84.5 on CyberGym, 54.4 on ExploitBench, and 105/130 completed ExploitGym tasks under normalized two-hour/six-hour budgets.
- 1M-Token Coding Workflows: The GLM Coding Plan supports a 1M-token context. Claude Code users enable it with the
glm-5.3[1m]model name and a 1,000,000-token auto-compaction window.
Best Use Cases
- Complex Software Engineering: Repository-scale implementation, debugging, performance optimization, and test-fix-verify loops that require sustained work across many files and tools.
- Long-Horizon Coding Agents: ZCode, Claude Code, Codex, OpenCode, Cline, and other configurable agents that can use Z.AI's Anthropic-compatible or OpenAI-compatible Coding Plan endpoints.
- Authorized Security Research: Vulnerability discovery, validation, and exploit-chain analysis in systems the operator is permitted to test.
- Tool-Driven Professional Workflows: Multi-step engineering and research tasks with executable environments, objective verification, and iterative feedback.
Capabilities and Limitations
| Capability | Description |
|---|---|
| Reasoning | Thinking is always enabled. reasoning_effort supports low, high, and max; the default is max, which Z.AI recommends for coding tasks. |
| Creative Writing | General text generation is available. |
| Coding | Z.AI reports Terminal-Bench 2.1: 88.2, Terminal-Bench 3.0: 28.3, DeepSWE v1.1: 66.9, NL2Repo: 58.0, FrontierSWE: 78.1, and SWE-Marathon v1.1: 42.5. |
| Multimodal | Text input and text output. |
| Response Speed | Not published as a guaranteed API rate. |
| Context Window | Up to 1M tokens in GLM Coding Plan workflows. Claude Code requires the glm-5.3[1m] suffix to enable the 1M-token mode. |
| Max Output | Not published as a general API limit. |
| Tool Use | Designed and evaluated in tool-using coding-agent harnesses; available to Coding Plan users through ZCode and configurable Anthropic-compatible or OpenAI-compatible agents. |
| Multilingual | Natural-language prompting is supported. |
Known Limitations
- Native GLM-5.3 API requests do not support
thinking.type: "disabled"; applications must enable thinking and can choosereasoning_effort: "low"for lighter reasoning. The Coding Plan compatibility layer may automatically map disabled thinking tolow. - The model is text-only; image, audio, and video inputs are not advertised for GLM-5.3.
Standard Pricing
The token prices below are shown in USD per 1 million tokens; web search is billed in USD per use.
| Model | Input (USD / 1M Tokens) | Cache Write (USD / 1M Tokens) | Cache Read (USD / 1M Tokens) | Output (USD / 1M Tokens) | Web Search (USD / use) |
|---|---|---|---|---|---|
| GLM-5.3 | $1.40 | $1.40 | $0.28 | $4.40 | - |
Credits settlement: B.AI converts charges at 1 USD = 1,000,000 Credits and deducts Credits from the account balance.
Prices shown in the documentation are B.AI standard reference prices for base billing purposes. B.AI may provide lower actual usage costs through top-up bonuses and account benefits. Specific prices, bonus Credits, and account benefits are subject to the platform display and final billing records.