Gemini 3 Flash vs GPT-5.6 Terra
Gemini 3 Flash 
GPT-5.6 Terra Verdict
- GPT-5.6 Terra (xhigh) leads on quality: 64.4 vs 61.6.
- Gemini 3 Flash (thinking) is stronger in instruction following, knowledge, multimodal.
- GPT-5.6 Terra (xhigh) is stronger in agents & tools, composite, long context, coding, human preference, maths, reasoning.
- Gemini 3 Flash (thinking) is 4.0× cheaper ($1.13 vs $4.50 per 1M blended).
- Gemini 3 Flash (thinking) streams 2.3× faster (180 vs 79 tokens per second).
| Metric | Gemini 3 Flash (thinking) | GPT-5.6 Terra (xhigh) |
|---|---|---|
| BenchLeader Index | 61.6 | 64.4 |
| Agents & tools score | 67.4 | 69.8 |
| Composite score | 62.3 | 77.3 |
| Instruction following score | 75.4 | 65.3 |
| Knowledge score | 69.0 | 61.0 |
| Long context score | 65.5 | 66.0 |
| Multimodal score | 64.4 | 63.0 |
| Coding score | – | 63.7 |
| Human preference score | – | 66.7 |
| Maths score | – | 71.0 |
| Reasoning score | – | 58.6 |
| Blended price $/M | $1.13 | $4.50 |
| Output speed | 180 tok/s | 79 tok/s |
| Time to first answer | 6.1 s | 33.6 s |
| Context window | 1M | 1M |
| SimpleBench | – | 48.9% |
| SciCode | – | 51.6% |
| ProofBench | – | 74.0% |
| LMArena Text | – | 1466 |
| LMArena Hard Prompts | – | 1491 |
| LMArena Coding | – | 1519 |
| LMArena WebDev | – | 1521 |
| LMArena Vision | – | 1269 |
| LMArena Agent | – | 1.5 |
| AA Intelligence Index | 26.3 | 38.2 |
| IFBench | 78.0% | 66.3% |
| AA-LCR | 78.0% | 79.0% |
| MMMU-Pro | 79.9% | 79.5% |
| AA-Omniscience | 10.1 | -3.0 |
| Terminal-Bench Hard | 38.6% | 62.9% |
| GPQA Diamond (AA) | 89.8% | 90.8% |
| Humanity's Last Exam (AA) | 36.6% | 41.9% |
| SciCode (AA) | – | 52.3% |
| τ²-Bench Telecom (AA) | 80.4% | 80.4% |
| LiveCodeBench | – | 85.9% |
| MMLU-Pro | – | 86.7% |
| IOI | – | 65.3% |
| CorpFin | – | 65.3% |
| TaxEval | – | 76.2% |
| GPQA Diamond (Vals) | – | 90.9% |
| ARC-AGI-1 | – | 94.0% |
| ARC-AGI-2 | – | 74.2% |
| ARC-AGI-3 | – | 0.7% |
Data as of 2026-09-10. Best configuration of each model; every score links to its source on the model pages.
Gemini 3 Flash vs GPT-5.6 Terra: questions
- Is Gemini 3 Flash better than GPT-5.6 Terra?
- GPT-5.6 Terra (xhigh) leads on quality: 64.4 vs 61.6. The BenchLeader Index combines every independent quality benchmark; GPT-5.6 Terra (xhigh) is ahead overall as of 2026-09-10, but check the category scores for your use.
- Is Gemini 3 Flash better than GPT-5.6 Terra for agentic tasks?
- GPT-5.6 Terra scores higher in agentic tasks (70 vs 67 on the category index, where 50 is average).
- Which is cheaper, Gemini 3 Flash or GPT-5.6 Terra?
- Gemini 3 Flash is cheaper: $1.13 against $4.50 per million tokens, blended at three input tokens per output token.
- Which is faster, Gemini 3 Flash or GPT-5.6 Terra?
- Gemini 3 Flash streams faster: 180 against 79 output tokens per second.
- Which has the larger context window?
- Both accept 1M tokens of context.