OpenAI: GPT-6 Luna (batch) vs DeepSeek: DeepSeek Flash Latest
Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-09-27.
| OpenAI: GPT-6 Luna (batch) | DeepSeek: DeepSeek Flash Latest | |
|---|---|---|
| Vendor | openai | ~deepseek |
| Quality Score | 100 | 100 |
| Benchmark Score | 62.2 | - |
| Input Price | $0.05/M | $0.04/M |
| Output Price | $0.25/M | $0.29/M |
| Context Window | 1,050,000 | 1,048,576 |
| Max Output | 128,000 | 384,000 |
| Tool Calling | ✓ | ✓ |
| Structured Output | ✓ | ✓ |
| Reasoning Mode | ✓ | ✓ |
| Vision | ✓ | ✓ |
| Audio | - | - |
| Benchmark Scores | ||
| ai_index | 61.5 | - |
The verdict
For a sample job of 1 million input tokens and 250,000 output tokens, DeepSeek Flash Latest costs $0.11 and GPT-6 Luna (batch) costs $0.11, so DeepSeek Flash Latest 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.
Across the 18 tasks where they differ, GPT-6 Luna (batch) scores higher on 18 (SQL Generation, Code Review, Code Completion and others).
Pick GPT-6 Luna (batch) if you need the stronger all-round task scores; pick DeepSeek Flash Latest if you need lower cost.
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 (batch) | DeepSeek: DeepSeek Flash Latest |
|---|---|---|
| SQL Generation | 141 | 134 |
| Code Review | 143 | 132 |
| Code Completion | 133 | 131 |
| Code Refactoring | 145 | 136 |
| Bug Fixing | 147 | 136 |
| Unit Test Generation | 131 | 124 |
| Code Documentation | 137 | 131 |
| Regex Writing | 126 | 119 |
| CI/CD Pipelines | 127 | 120 |
| Frontend Component Design | 129 | 122 |
| Data Analysis | 133 | 124 |
| CSV / Spreadsheet Cleanup | 136 | 134 |
| ETL Scripting | 136 | 128 |
| OCR / Document Parsing | 134 | 131 |
| Table Extraction from PDFs | 134 | 131 |
| Long-Document Summarization | 147 | 138 |
| Short-Form Summarization | 127 | 123 |
| Blog Post Writing | 129 | 122 |
Scores reflect capability match + benchmark data + pricing for each task. Methodology →