Z.ai's large-scale reasoning flagship for complex software engineering and long-horizon agent tasks.
Anthropic's new flagship for demanding reasoning, coding, and long-horizon agentic work, succeeding Claude Opus 5.
No shared demos for these models yet.
No captured outputs for these models yet.
Both GLM 5.3 and Claude Opus 5.5 are capable AI models. The best choice depends on your specific use case: consider pricing, context window, speed, and which capabilities (vision, reasoning, audio) you need.
GLM 5.3 has a lower blended cost. GLM 5.3: $0.22 input / $3.39 output. Claude Opus 5.5: $4.00 input / $20.00 output.
GLM 5.3 has a larger context window: GLM 5.3 supports 1M tokens vs Claude Opus 5.5 at 1M tokens.
Claude Opus 5.5 supports vision/image input, but GLM 5.3 does not.
Key differences: GLM 5.3 is significantly cheaper; only Claude Opus 5.5 supports vision input. Compare full specs on this page.
If cost is your priority, choose the cheaper option. If you need the highest intelligence for complex tasks, pick the higher-scoring model. For long documents or codebases, choose the larger context window. You can try both GLM 5.3 and Claude Opus 5.5 for free on idapt.app to see which performs better for your specific needs.