OpenAI: GPT-6 Luna vs DeepSeek: DeepSeek V4.1 Flash (batch)
Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-10-04.
| OpenAI: GPT-6 Luna | DeepSeek: DeepSeek V4.1 Flash (batch) | |
|---|---|---|
| Vendor | openai | deepseek |
| Quality Score | 100 | 100 |
| Benchmark Score | 63.8 | 66.3 |
| Input Price | $0.10/M | $0.11/M |
| Output Price | $0.50/M | $0.34/M |
| Context Window | 1,050,000 | 1,048,576 |
| Max Output | 128,000 | 131,072 |
| Tool Calling | ✓ | ✓ |
| Structured Output | ✓ | ✓ |
| Reasoning Mode | ✓ | ✓ |
| Vision | ✓ | ✓ |
| Audio | - | - |
| Benchmark Scores | ||
| ai_index | 62.9 | 65.1 |
The verdict
For a sample job of 1 million input tokens and 250,000 output tokens, DeepSeek V4.1 Flash (batch) costs $0.20 and GPT-6 Luna costs $0.23, so DeepSeek V4.1 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.
On our blended benchmark score DeepSeek V4.1 Flash (batch) leads 66.3 to 63.8.
Across the 19 tasks where they differ, DeepSeek V4.1 Flash (batch) on 19 (SQL Generation, Code Review, Code Completion and others).
Pick DeepSeek V4.1 Flash (batch) if you need lower cost, benchmark performance 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 | DeepSeek: DeepSeek V4.1 Flash (batch) |
|---|---|---|
| SQL Generation | 141 | 141 |
| Code Review | 144 | 144 |
| Code Completion | 133 | 133 |
| Code Refactoring | 146 | 146 |
| Bug Fixing | 148 | 148 |
| Unit Test Generation | 131 | 131 |
| Code Documentation | 137 | 137 |
| Regex Writing | 126 | 126 |
| CI/CD Pipelines | 127 | 127 |
| Frontend Component Design | 129 | 129 |
| Data Analysis | 133 | 133 |
| CSV / Spreadsheet Cleanup | 136 | 136 |
| ETL Scripting | 136 | 137 |
| Bulk Data Labeling | 129 | 129 |
| OCR / Document Parsing | 134 | 134 |
| Table Extraction from PDFs | 134 | 134 |
| Long-Document Summarization | 148 | 148 |
| Short-Form Summarization | 127 | 127 |
| Blog Post Writing | 129 | 129 |
Scores reflect capability match + benchmark data + pricing for each task. Methodology →