Gemini 3.8 Flash vs Grok 4.3
Gemini 3.8 Flash 
Grok 4.3 Verdict
- Gemini 3.8 Flash (medium) leads on quality: 63.6 vs 60.7.
- Gemini 3.8 Flash (medium) is stronger in coding, composite, knowledge, long context, multimodal.
- Grok 4.3 (medium) is stronger in agents & tools, instruction following.
- They cost about the same ($1.50 per 1M blended).
| Metric | Gemini 3.8 Flash (medium) | Grok 4.3 (medium) |
|---|---|---|
| BenchLeader Index | 63.6 | 60.7 |
| Coding score | 63.8 | – |
| Composite score | 79.6 | 60.3 |
| Knowledge score | 77.7 | 72.1 |
| Long context score | 68.6 | 64.0 |
| Multimodal score | 68.8 | 60.2 |
| Agents & tools score | – | 60.1 |
| Instruction following score | – | 80.0 |
| Blended price $/M | $1.50 | $1.56 |
| Output speed | 90 tok/s | 112 tok/s |
| Time to first answer | 11.7 s | 12.1 s |
| Context window | 1M | 1M |
| SciCode | 54.4% | – |
| AA Intelligence Index | 40 | 24.8 |
| IFBench | – | 83.3% |
| AA-LCR | 84.0% | 75.0% |
| MMMU-Pro | 84.2% | 75.8% |
| AA-Omniscience | 28.6 | 16.7 |
| Terminal-Bench Hard | – | 30.3% |
| GPQA Diamond (AA) | 93.5% | 89.0% |
| Humanity's Last Exam (AA) | 42.1% | 30.0% |
| SciCode (AA) | 55.1% | – |
| τ²-Bench Telecom (AA) | – | 91.2% |
Data as of 2026-09-10. Best configuration of each model; every score links to its source on the model pages.
Gemini 3.8 Flash vs Grok 4.3: questions
- Is Gemini 3.8 Flash better than Grok 4.3?
- Gemini 3.8 Flash (medium) leads on quality: 63.6 vs 60.7. The BenchLeader Index combines every independent quality benchmark; Gemini 3.8 Flash (medium) is ahead overall as of 2026-09-10, but check the category scores for your use.
- Which is cheaper, Gemini 3.8 Flash or Grok 4.3?
- Gemini 3.8 Flash is cheaper: $1.50 against $1.56 per million tokens, blended at three input tokens per output token.
- Which is faster, Gemini 3.8 Flash or Grok 4.3?
- Grok 4.3 streams faster: 112 against 90 output tokens per second.
- Which has the larger context window?
- Both accept 1M tokens of context.