Gemini 3.5 Flash vs GPT-5.2
Gemini 3.5 Flash 
GPT-5.2 Verdict
- Gemini 3.5 Flash (medium) leads on quality: 64.1 vs 61.6.
- Gemini 3.5 Flash (medium) is stronger in agents & tools, coding, composite, instruction following, knowledge, multimodal, reasoning.
- GPT-5.2 is stronger in human preference, long context.
- Gemini 3.5 Flash (medium) is 1.4× cheaper ($3.38 vs $4.81 per 1M blended).
- Gemini 3.5 Flash (medium) streams 3.2× faster (217 vs 68 tokens per second).
| Metric | Gemini 3.5 Flash (medium) | GPT-5.2 |
|---|---|---|
| BenchLeader Index | 64.1 | 61.6 |
| Agents & tools score | 68.0 | 61.2 |
| Coding score | 58.9 | 53.7 |
| Composite score | 71.5 | 67.5 |
| Human preference score | 67.8 | 67.9 |
| Instruction following score | 72.5 | 67.4 |
| Knowledge score | 74.0 | 61.1 |
| Long context score | 63.6 | 67.9 |
| Multimodal score | 67.6 | 59.9 |
| Reasoning score | 67.1 | 61.3 |
| Blended price $/M | $3.38 | $4.81 |
| Output speed | 217 tok/s | 68 tok/s |
| Time to first answer | 15.5 s | 129.4 s |
| Context window | 1M | 400k |
| Humanity's Last Exam | – | 27.8% |
| Terminal-Bench | – | 64.9% |
| SimpleBench | – | 45.8% |
| Remote Labor Index | – | 2.1% |
| APEX-Agents | – | 23.0% |
| Epoch Capabilities Index | – | 153.5 |
| LMArena Text | 1476 | 1476 |
| LMArena Hard Prompts | 1493 | 1497 |
| LMArena Coding | 1503 | 1515 |
| LMArena WebDev | 1491 | 1417 |
| LMArena Vision | 1306 | 1268 |
| AA Intelligence Index | 33.6 | 30.4 |
| IFBench | 74.6% | 75.4% |
| AA-LCR | 74.3% | 82.7% |
| MMMU-Pro | 83.9% | – |
| AA-Omniscience | 20.8 | -0.9 |
| Terminal-Bench Hard | 39.4% | 47.0% |
| GPQA Diamond (AA) | 92.1% | 90.3% |
| Humanity's Last Exam (AA) | 41.3% | 37.7% |
| τ²-Bench Telecom (AA) | 95.6% | 84.8% |
| SWE-Bench Pro | – | 29.9% |
| VISTA | – | 46.6% |
| MultiNRC | – | 42.2% |
| TutorBench | – | 53.5% |
| Kagi LLM Benchmark | – | 73.3% |
| SWE-bench Verified (bash only) | – | 69.0% |
| ARC-AGI-1 | – | 94.5% |
| ARC-AGI-2 | – | 72.9% |
| BFCL Overall | – | 55.9% |
Data as of 2026-09-10. Best configuration of each model; every score links to its source on the model pages.
Gemini 3.5 Flash vs GPT-5.2: questions
- Is Gemini 3.5 Flash better than GPT-5.2?
- Gemini 3.5 Flash (medium) leads on quality: 64.1 vs 61.6. The BenchLeader Index combines every independent quality benchmark; Gemini 3.5 Flash (medium) is ahead overall as of 2026-09-10, but check the category scores for your use.
- Is Gemini 3.5 Flash better than GPT-5.2 for coding?
- Gemini 3.5 Flash scores higher in coding (59 vs 54 on the category index, where 50 is average).
- Is Gemini 3.5 Flash better than GPT-5.2 for agentic tasks?
- Gemini 3.5 Flash scores higher in agentic tasks (68 vs 61 on the category index, where 50 is average).
- Which is cheaper, Gemini 3.5 Flash or GPT-5.2?
- Gemini 3.5 Flash is cheaper: $3.38 against $4.81 per million tokens, blended at three input tokens per output token.
- Which is faster, Gemini 3.5 Flash or GPT-5.2?
- Gemini 3.5 Flash streams faster: 217 against 68 output tokens per second.
- Which has the larger context window?
- Gemini 3.5 Flash accepts more context: 1M against 400k tokens.