Google: Gemini 3.7 Flash (batch) vs OpenAI: GPT-5.6 Luna (batch)
Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-09-28.
| Google: Gemini 3.7 Flash (batch) | OpenAI: GPT-5.6 Luna (batch) | |
|---|---|---|
| Vendor | openai | |
| Quality Score | 100 | 100 |
| Benchmark Score | 65.5 | 62.3 |
| Input Price | $0.38/M | $0.10/M |
| Output Price | $1.88/M | $0.60/M |
| Context Window | 1,048,576 | 1,050,000 |
| Max Output | 65,536 | 128,000 |
| Tool Calling | ✓ | ✓ |
| Structured Output | ✓ | ✓ |
| Reasoning Mode | ✓ | ✓ |
| Vision | ✓ | ✓ |
| Audio | ✓ | - |
| Benchmark Scores | ||
| ai_index | 64.4 | 61.6 |
The verdict
For a sample job of 1 million input tokens and 250,000 output tokens, GPT-5.6 Luna (batch) costs $0.25 and Gemini 3.7 Flash (batch) costs $0.84, so GPT-5.6 Luna (batch) is about 3.4 times cheaper for the same work.
Both take in a similar amount of text: 1,048,576 and 1,050,000 tokens, about 1,573 and 1,575 pages.
Only Gemini 3.7 Flash (batch) offers audio input and video input.
On our blended benchmark score Gemini 3.7 Flash (batch) leads 65.5 to 62.3.
Across the 18 tasks where they differ, Gemini 3.7 Flash (batch) scores higher on 13 (SQL Generation, Code Review, Code Refactoring and others), GPT-5.6 Luna (batch) on 5 (Code Completion, Code Documentation, JSON Extraction and others).
Gemini 3.7 Flash (batch) was released in August 2026 and GPT-5.6 Luna (batch) in July 2026.
Pick Gemini 3.7 Flash (batch) if you need audio input, video input, benchmark performance or the stronger all-round task scores; pick GPT-5.6 Luna (batch) 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 | Google: Gemini 3.7 Flash (batch) | OpenAI: GPT-5.6 Luna (batch) |
|---|---|---|
| SQL Generation | 141 | 141 |
| Code Review | 144 | 143 |
| Code Completion | 132 | 133 |
| Code Refactoring | 146 | 145 |
| Bug Fixing | 148 | 147 |
| Unit Test Generation | 131 | 131 |
| Code Documentation | 137 | 137 |
| CI/CD Pipelines | 127 | 127 |
| Frontend Component Design | 129 | 129 |
| Data Analysis | 133 | 133 |
| ETL Scripting | 137 | 136 |
| JSON Extraction | 131 | 131 |
| Bulk Data Labeling | 129 | 129 |
| OCR / Document Parsing | 134 | 134 |
| Table Extraction from PDFs | 134 | 134 |
| Long-Document Summarization | 148 | 147 |
| Short-Form Summarization | 126 | 126 |
| Blog Post Writing | 129 | 129 |
Scores reflect capability match + benchmark data + pricing for each task. Methodology →