Gemini 3.8 Flash vs GPT-5.4 Pro
Gemini 3.8 Flash 
GPT-5.4 Pro Verdict
- Gemini 3.8 Flash (medium) and GPT-5.4 Pro are level on quality (63.5 vs 64.2).
- Gemini 3.8 Flash (medium) is stronger in coding, composite, knowledge, long context.
- GPT-5.4 Pro is stronger in multimodal, instruction following, reasoning.
- Gemini 3.8 Flash (medium) is 45× cheaper ($1.50 vs $67.50 per 1M blended).
- Gemini 3.8 Flash (medium) streams 272.9× faster (273 vs 1 tokens per second).
| Metric | Gemini 3.8 Flash (medium) | GPT-5.4 Pro |
|---|---|---|
| BenchLeader Index | 63.5 | 64.2 |
| Coding score | 63.6 | – |
| Composite score | 79.4 | – |
| Knowledge score | 77.6 | 73.2 |
| Long context score | 68.7 | – |
| Multimodal score | 68.9 | 69.8 |
| Instruction following score | – | 67.3 |
| Reasoning score | – | 75.1 |
| Blended price $/M | $1.50 | $67.50 |
| Output speed | 273 tok/s | 1 tok/s |
| Time to first answer | 13.8 s | 6.7 s |
| Context window | 1M | 1.1M |
| Humanity's Last Exam | – | 44.3% |
| SimpleBench | – | 74.1% |
| SciCode | 54.4% | – |
| Epoch Capabilities Index | – | 158.9 |
| AA Intelligence Index | 40 | – |
| AA-LCR | 84.0% | – |
| MMMU-Pro | 84.2% | – |
| AA-Omniscience | 28.6 | – |
| GPQA Diamond (AA) | 93.5% | – |
| Humanity's Last Exam (AA) | 42.1% | – |
| SciCode (AA) | 55.1% | – |
| MultiChallenge | – | 69.2% |
| VISTA | – | 53.9% |
| MultiNRC | – | 62.3% |
| TutorBench | – | 56.6% |
Data as of 2026-09-09. Best configuration of each model; every score links to its source on the model pages.