head-to-head
OpenAI: GPT-5.6 Luna vs StepFun: Step 3.7 Flash
Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-09-23.
| OpenAI: GPT-5.6 Luna | StepFun: Step 3.7 Flash | |
|---|---|---|
| Vendor | openai | stepfun |
| Quality Score | 100 | 100 |
| Benchmark Score | 62.3 | 29.1 |
| Input Price | $0.20/M | $0.20/M |
| Output Price | $1.20/M | $1.15/M |
| Context Window | 1,050,000 | 262,144 |
| Max Output | 128,000 | 230,400 |
| Tool Calling | ✓ | ✓ |
| Structured Output | ✓ | ✓ |
| Reasoning Mode | ✓ | ✓ |
| Vision | ✓ | ✓ |
| Audio | - | - |
| Benchmark Scores | ||
| ai_index | 61.6 | 32.1 |
Who wins by task?
| Task | OpenAI: GPT-5.6 Luna | StepFun: Step 3.7 Flash |
|---|---|---|
| SQL Generation | 141 | 135 |
| Code Review | 143 | 132 |
| Code Completion | 133 | 129 |
| Code Refactoring | 145 | 132 |
| Bug Fixing | 147 | 136 |
| Unit Test Generation | 131 | 125 |
| Code Documentation | 137 | 129 |
| Regex Writing | 125 | 122 |
| CI/CD Pipelines | 127 | 121 |
| Frontend Component Design | 129 | 125 |
| Data Analysis | 133 | 128 |
| CSV / Spreadsheet Cleanup | 136 | 129 |
| ETL Scripting | 136 | 127 |
| OCR / Document Parsing | 134 | 129 |
| Table Extraction from PDFs | 134 | 129 |
| Long-Document Summarization | 147 | 134 |
| Short-Form Summarization | 126 | 125 |
| Blog Post Writing | 129 | 123 |
Scores reflect capability match + benchmark data + pricing for each task. Methodology →
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