OpenAI: GPT-6 Luna Pro (batch) vs Z.ai: GLM 5.3 Flash (batch)
Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-11-07.
| OpenAI: GPT-6 Luna Pro (batch) | Z.ai: GLM 5.3 Flash (batch) | |
|---|---|---|
| Vendor | openai | z-ai |
| Quality Score | 100 | 100 |
| Input Price | $0.05/M | $0.05/M |
| Output Price | $0.25/M | $0.18/M |
| Context Window | 1,050,000 | 1,048,576 |
| Max Output | 128,000 | 131,072 |
| Tool Calling | ✓ | ✓ |
| Structured Output | ✓ | ✓ |
| Reasoning Mode | ✓ | ✓ |
| Vision | ✓ | ✓ |
| Audio | - | - |
The verdict
For a sample job of 1 million input tokens and 250,000 output tokens, GLM 5.3 Flash (batch) costs $0.095 and GPT-6 Luna Pro (batch) costs $0.11, so GLM 5.3 Flash (batch) is slightly cheaper for the same work.
Both take in a similar amount of text: 1,050,000 and 1,048,576 tokens, about 1,575 and 1,573 pages.
Only GLM 5.3 Flash (batch) offers video input.
Across the 5 tasks where they differ, GLM 5.3 Flash (batch) on 5 (Code Completion, Code Documentation, Regex Writing and others).
GPT-6 Luna Pro (batch) was released in September 2026 and GLM 5.3 Flash (batch) in August 2026.
Pick GLM 5.3 Flash (batch) if you need lower cost, video input or the stronger all-round task scores.
Costs use current list prices per million tokens; page counts assume about 0.75 words per token and 500 words per page.
Who wins by task?
| Task | OpenAI: GPT-6 Luna Pro (batch) | Z.ai: GLM 5.3 Flash (batch) |
|---|---|---|
| Code Completion | 131 | 132 |
| Code Documentation | 131 | 132 |
| Regex Writing | 119 | 120 |
| JSON Extraction | 131 | 132 |
| Short-Form Summarization | 123 | 124 |
Scores reflect capability match + benchmark data + pricing for each task. Methodology →