OpenAI: GPT-5.6 Terra Pro (batch) vs Google: Gemini 3.5 Flash (batch)
Side-by-side comparison of specs, pricing, benchmark scores, and task rankings. Updated 2026-11-07.
| OpenAI: GPT-5.6 Terra Pro (batch) | Google: Gemini 3.5 Flash (batch) | |
|---|---|---|
| Vendor | openai | |
| Quality Score | 100 | 100 |
| Benchmark Score | - | 84.2 |
| Input Price | $1.00/M | $0.75/M |
| Output Price | $6.00/M | $4.50/M |
| Context Window | 1,050,000 | 1,048,576 |
| Max Output | 128,000 | 65,536 |
| Tool Calling | ✓ | ✓ |
| Structured Output | ✓ | ✓ |
| Reasoning Mode | ✓ | ✓ |
| Vision | ✓ | ✓ |
| Audio | - | ✓ |
| Benchmark Scores | ||
| ai_index | - | 82.8 |
| ai_index_agentic | - | 61.8 |
| ai_index_coding | - | 100.0 |
The verdict
For a sample job of 1 million input tokens and 250,000 output tokens, Gemini 3.5 Flash (batch) costs $1.88 and GPT-5.6 Terra Pro (batch) costs $2.50, so Gemini 3.5 Flash (batch) is about 1.3 times 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 Gemini 3.5 Flash (batch) offers audio input and video input.
Across the 20 tasks where they differ, Gemini 3.5 Flash (batch) on 20 (SQL Generation, Code Review, Code Completion and others).
GPT-5.6 Terra Pro (batch) was released in July 2026 and Gemini 3.5 Flash (batch) in May 2026.
Pick Gemini 3.5 Flash (batch) if you need lower cost, audio input, 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-5.6 Terra Pro (batch) | Google: Gemini 3.5 Flash (batch) |
|---|---|---|
| SQL Generation | 133 | 169 |
| Code Review | 132 | 164 |
| Code Completion | 118 | 132 |
| Code Refactoring | 136 | 162 |
| Bug Fixing | 136 | 176 |
| Unit Test Generation | 124 | 152 |
| Code Documentation | 130 | 142 |
| Regex Writing | 118 | 134 |
| CI/CD Pipelines | 120 | 143 |
| Frontend Component Design | 122 | 145 |
| Data Analysis | 124 | 167 |
| CSV / Spreadsheet Cleanup | 133 | 153 |
| ETL Scripting | 128 | 152 |
| JSON Extraction | 122 | 147 |
| Bulk Data Labeling | 119 | 134 |
| OCR / Document Parsing | 131 | 146 |
| Table Extraction from PDFs | 131 | 146 |
| Long-Document Summarization | 137 | 158 |
| Short-Form Summarization | 114 | 130 |
| Blog Post Writing | 121 | 139 |
Scores reflect capability match + benchmark data + pricing for each task. Methodology →