GLM-5.3
Z.ai flagship. Text-only input. Migration: requests with thinking disabled fail - set enabled + reasoning_effort low. Coding Plan base URL is https://api.z.ai/api/coding/paas/v4. Release day not verified (OpenRouter 2026-08-18, HF 2026-08-25). GLM-5.2 (same price, MIT weights) still listed.
- Context window
- 1,000,000 tokens
- Max output
- 128,000 tokens
- Input
- text
- Output
- text
- License
- glm-5.3 (custom)
- Pricing
- input: $1.4 · output: $4.4 · cache read: $0.26 (per 1M tokens (USD)) source
- Verified
- 2026-09-29
How to call it
| Provider | Model id | Endpoint / URL | Docs |
|---|---|---|---|
| Z.ai API | glm-5.3 | https://api.z.ai/api/paas/v4 | docs |
| Z.ai API (Anthropic format) | glm-5.3 | https://api.z.ai/api/anthropic | docs |
| Alibaba Cloud Model Studio | ZHIPU/GLM-5.3 | — | docs |
| OpenRouter | z-ai/glm-5.3 | openrouter.ai/z-ai/glm-5.3 | — |
| Hugging Face | — | huggingface.co/zai-org/GLM-5.3 | — |
| Web app | — | chat.z.ai | — |
Notable capabilities (4)
- Post-training-only jump in coding: Same base as GLM-5.2; Z.ai reports +50% on its Code Bench and open-model SOTA on Terminal Bench 3.0 and Agents' Last Exam (CLI). source
- Emergent cyber capability: Best CyberGym vulnerability-discovery score to date per Z.ai; exploitation benchmark scores more than double GLM-5.2's. source
- Always-on reasoning with effort levels: thinking.type disabled no longer allowed; reasoning_effort low/high/max (default max). source
- Coding Plan integration: Available in the GLM Coding Plan (points-based; off-peak/weekend calls cost 50% points) for Claude Code, Cline, OpenCode etc. source
Z.ai's top model for long-horizon software engineering, terminal agents and security research; 1M context, 128K output.
curl https://api.z.ai/api/paas/v4/chat/completions \
-H "Authorization: Bearer $ZAI_API_KEY" -H "Content-Type: application/json" \
-d '{"model":"glm-5.3","thinking":{"type":"enabled"},"reasoning_effort":"max","messages":[{"role":"user","content":"Hello"}]}'
Sources: https://docs.z.ai/guides/llm/glm-5.3 · https://docs.z.ai/guides/overview/pricing · https://huggingface.co/zai-org/GLM-5.3