Gemini 3 Flash vs GPT-5 Pro
Gemini 3 Flash 
GPT-5 Pro Verdict
- Gemini 3 Flash (thinking) and GPT-5 Pro are level on quality (61.6 vs 60.8).
- Gemini 3 Flash (thinking) is stronger in agents & tools, composite, instruction following, knowledge, long context.
- GPT-5 Pro is stronger in multimodal, reasoning.
- Gemini 3 Flash (thinking) is 37× cheaper ($1.13 vs $41.25 per 1M blended).
| Metric | Gemini 3 Flash (thinking) | GPT-5 Pro |
|---|---|---|
| BenchLeader Index | 61.6 | 60.8 |
| Agents & tools score | 67.4 | – |
| Composite score | 62.3 | – |
| Instruction following score | 75.4 | – |
| Knowledge score | 69.0 | 68.0 |
| Long context score | 65.5 | – |
| Multimodal score | 64.4 | 67.4 |
| Reasoning score | – | 57.6 |
| Blended price $/M | $1.13 | $41.25 |
| Output speed | 180 tok/s | – |
| Time to first answer | 6.1 s | – |
| Context window | 1M | 400k |
| Humanity's Last Exam | – | 31.6% |
| SimpleBench | – | 61.6% |
| Epoch Capabilities Index | – | 150.3 |
| AA Intelligence Index | 26.3 | – |
| IFBench | 78.0% | – |
| AA-LCR | 78.0% | – |
| MMMU-Pro | 79.9% | – |
| AA-Omniscience | 10.1 | – |
| Terminal-Bench Hard | 38.6% | – |
| GPQA Diamond (AA) | 89.8% | – |
| Humanity's Last Exam (AA) | 36.6% | – |
| τ²-Bench Telecom (AA) | 80.4% | – |
| PRBench Finance | – | 51.1% |
| PRBench Legal | – | 49.9% |
| VISTA | – | 52.4% |
| MultiNRC | – | 65.2% |
| Kagi LLM Benchmark | – | 76.8% |
| ARC-AGI-1 | – | 70.2% |
| ARC-AGI-2 | – | 18.3% |
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 Pro: questions
- Is Gemini 3 Flash better than GPT-5 Pro?
- Gemini 3 Flash (thinking) and GPT-5 Pro are level on quality (61.6 vs 60.8). The BenchLeader Index combines every independent quality benchmark; Gemini 3 Flash (thinking) is ahead overall as of 2026-09-10, but check the category scores for your use.
- Which is cheaper, Gemini 3 Flash or GPT-5 Pro?
- Gemini 3 Flash is cheaper: $1.13 against $41.25 per million tokens, blended at three input tokens per output token.
- Which has the larger context window?
- Gemini 3 Flash accepts more context: 1M against 400k tokens.