Claude Sonnet 5 vs Gemini 3 Flash
Claude Sonnet 5 
Gemini 3 Flash Verdict
- Claude Sonnet 5 (high) and Gemini 3 Flash (thinking) are level on quality (61.4 vs 61.6).
- Claude Sonnet 5 (high) is stronger in coding, composite, human preference, reasoning.
- Gemini 3 Flash (thinking) is stronger in agents & tools, knowledge, long context, multimodal, instruction following.
- Gemini 3 Flash (thinking) is 3.6× cheaper ($1.13 vs $4.00 per 1M blended).
- Gemini 3 Flash (thinking) streams 3.0× faster (180 vs 60 tokens per second).
| Metric | Claude Sonnet 5 (high) | Gemini 3 Flash (thinking) |
|---|---|---|
| BenchLeader Index | 61.4 | 61.6 |
| Agents & tools score | 61.8 | 67.4 |
| Coding score | 61.6 | – |
| Composite score | 69.5 | 62.3 |
| Human preference score | 66.2 | – |
| Knowledge score | 62.4 | 69.0 |
| Long context score | 64.8 | 65.5 |
| Multimodal score | 63.1 | 64.4 |
| Reasoning score | 66.8 | – |
| Instruction following score | – | 75.4 |
| Blended price $/M | $4.00 | $1.13 |
| Output speed | 60 tok/s | 180 tok/s |
| Time to first answer | 10.0 s | 6.1 s |
| Context window | 1M | 1M |
| SciCode | 48.6% | – |
| WeirdML | 68.8% | – |
| LMArena Text | 1462 | – |
| LMArena Hard Prompts | 1490 | – |
| LMArena Coding | 1521 | – |
| LMArena WebDev | 1538 | – |
| LMArena Vision | 1278 | – |
| LMArena Agent | 6.3 | – |
| AA Intelligence Index | 32.0 | 26.3 |
| IFBench | – | 78.0% |
| AA-LCR | 76.7% | 78.0% |
| MMMU-Pro | – | 79.9% |
| AA-Omniscience | -3.7 | 10.1 |
| Terminal-Bench Hard | – | 38.6% |
| GPQA Diamond (AA) | – | 89.8% |
| Humanity's Last Exam (AA) | 35.7% | 36.6% |
| SciCode (AA) | 54.3% | – |
| τ²-Bench Telecom (AA) | – | 80.4% |
Data as of 2026-09-10. Best configuration of each model; every score links to its source on the model pages.
Claude Sonnet 5 vs Gemini 3 Flash: questions
- Is Claude Sonnet 5 better than Gemini 3 Flash?
- Claude Sonnet 5 (high) and Gemini 3 Flash (thinking) are level on quality (61.4 vs 61.6). 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.
- Is Claude Sonnet 5 better than Gemini 3 Flash for agentic tasks?
- Gemini 3 Flash scores higher in agentic tasks (67 vs 62 on the category index, where 50 is average).
- Which is cheaper, Claude Sonnet 5 or Gemini 3 Flash?
- Gemini 3 Flash is cheaper: $1.13 against $4.00 per million tokens, blended at three input tokens per output token.
- Which is faster, Claude Sonnet 5 or Gemini 3 Flash?
- Gemini 3 Flash streams faster: 180 against 60 output tokens per second.
- Which has the larger context window?
- Both accept 1M tokens of context.