Claude Sonnet 5 vs Grok 4.5
Claude Sonnet 5 
Grok 4.5 Verdict
- Grok 4.5 leads on quality: 63.5 vs 61.4.
- Claude Sonnet 5 (high) is stronger in agents & tools, coding, composite.
- Grok 4.5 is stronger in human preference, knowledge, long context, multimodal, reasoning.
- Grok 4.5 is 1.3× cheaper ($3.00 vs $4.00 per 1M blended).
| Metric | Claude Sonnet 5 (high) | Grok 4.5 |
|---|---|---|
| BenchLeader Index | 61.4 | 63.5 |
| Agents & tools score | 61.8 | 58.6 |
| Coding score | 61.6 | 59.8 |
| Composite score | 69.5 | 66.2 |
| Human preference score | 66.2 | 67.2 |
| Knowledge score | 62.4 | 76.2 |
| Long context score | 64.8 | 66.2 |
| Multimodal score | 63.1 | 64.9 |
| Reasoning score | 66.8 | 69.2 |
| Blended price $/M | $4.00 | $3.00 |
| Output speed | 60 tok/s | 52 tok/s |
| Time to first answer | 10.0 s | 13.6 s |
| Context window | 1M | 500k |
| SimpleBench | – | 70.0% |
| SciCode | 48.6% | – |
| WeirdML | 68.8% | 46.4% |
| APEX-Agents | – | 34.2% |
| FrontierCode | – | 42.4% |
| Epoch Capabilities Index | – | 153.9 |
| LMArena Text | 1462 | 1471 |
| LMArena Hard Prompts | 1490 | 1495 |
| LMArena Coding | 1521 | 1523 |
| LMArena WebDev | 1538 | 1556 |
| LMArena Vision | 1278 | 1291 |
| LMArena Agent | 6.3 | 3.9 |
| LiveBench | – | 75.8% |
| LiveBench Reasoning | – | 87.2% |
| LiveBench Coding | – | 68.6% |
| LiveBench Agentic Coding | – | 56.5% |
| LiveBench Mathematics | – | 90.8% |
| LiveBench Data Analysis | – | 73.0% |
| LiveBench Language | – | 82.8% |
| AA Intelligence Index | 32.0 | 39.1 |
| AA-LCR | 76.7% | 79.3% |
| MMMU-Pro | – | 80.4% |
| AA-Omniscience | -3.7 | 25.3 |
| GPQA Diamond (AA) | – | 93.1% |
| Humanity's Last Exam (AA) | 35.7% | 42.7% |
| SciCode (AA) | 54.3% | 55.0% |
| Kagi LLM Benchmark | – | 83.5% |
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 Grok 4.5: questions
- Is Claude Sonnet 5 better than Grok 4.5?
- Grok 4.5 leads on quality: 63.5 vs 61.4. The BenchLeader Index combines every independent quality benchmark; Grok 4.5 is ahead overall as of 2026-09-10, but check the category scores for your use.
- Is Claude Sonnet 5 better than Grok 4.5 for coding?
- Claude Sonnet 5 scores higher in coding (62 vs 60 on the category index, where 50 is average).
- Is Claude Sonnet 5 better than Grok 4.5 for agentic tasks?
- Claude Sonnet 5 scores higher in agentic tasks (62 vs 59 on the category index, where 50 is average).
- Which is cheaper, Claude Sonnet 5 or Grok 4.5?
- Grok 4.5 is cheaper: $3.00 against $4.00 per million tokens, blended at three input tokens per output token.
- Which is faster, Claude Sonnet 5 or Grok 4.5?
- Claude Sonnet 5 streams faster: 60 against 52 output tokens per second.
- Which has the larger context window?
- Claude Sonnet 5 accepts more context: 1M against 500k tokens.