Claude Opus 5 vs Claude Sonnet 4.5
Claude Opus 5 Verdict
- Claude Opus 5 leads on quality: 68.4 vs 57.9.
- Claude Opus 5 is stronger in agents & tools, coding, composite, human preference, knowledge, long context, maths, multimodal, reasoning.
- Claude Sonnet 4.5 (high) is 1.7× cheaper ($6.00 vs $10.00 per 1M blended).
- Claude Opus 5 streams 1.3× faster (53 vs 40 tokens per second).
| Metric | Claude Opus 5 | Claude Sonnet 4.5 (high) |
|---|---|---|
| BenchLeader Index | 68.4 | 57.9 |
| Agents & tools score | 71.5 | – |
| Coding score | 68.6 | 56.4 |
| Composite score | 85.3 | – |
| Human preference score | 78.2 | 65.3 |
| Knowledge score | 69.7 | – |
| Long context score | 63.7 | – |
| Maths score | 67.1 | – |
| Multimodal score | 68.9 | – |
| Reasoning score | 71.5 | 66.4 |
| Blended price $/M | $10.00 | $6.00 |
| Output speed | 53 tok/s | 40 tok/s |
| Time to first answer | 53.0 s | 1.2 s |
| Context window | 1M | 1M |
| GPQA Diamond | 92.9% | – |
| OTIS Mock AIME | 97.8% | – |
| SimpleBench | 80.6% | – |
| WeirdML | 86.3% | – |
| Epoch Capabilities Index | 162.6 | – |
| LMArena Text | – | 1456 |
| LMArena Hard Prompts | – | 1487 |
| LMArena Coding | – | 1520 |
| LMArena WebDev | – | 1393 |
| AA Intelligence Index | 50.7 | – |
| AA-LCR | 79.3% | – |
| MMMU-Pro | 84.7% | – |
| AA-Omniscience | 37.1 | – |
| GPQA Diamond (AA) | 93.2% | – |
| Humanity's Last Exam (AA) | 54.9% | – |
| SciCode (AA) | 56.4% | – |
| LiveCodeBench | 89.0% | – |
| MMLU-Pro | 91.6% | – |
| IOI | 84.3% | – |
| LegalBench | 87.0% | – |
| CorpFin | 73.2% | – |
| TaxEval | 75.1% | – |
| Terminal-Bench 2.1 (Vals) | 84.6% | – |
| SWE-bench (Vals) | 97.0% | – |
| GPQA Diamond (Vals) | 93.4% | – |
| Vals Index | 67.2 | – |
| HiL-Bench | 57.0% | – |
| EQ-Bench 4 | 1385 | – |
| SWE-bench Verified (bash only) | – | 71.4% |
Data as of 2026-09-13. Best configuration of each model; every score links to its source on the model pages.
Claude Opus 5 vs Claude Sonnet 4.5: questions
- Is Claude Opus 5 better than Claude Sonnet 4.5?
- Claude Opus 5 leads on quality: 68.4 vs 57.9. The BenchLeader Index combines every independent quality benchmark; Claude Opus 5 is ahead overall as of 2026-09-13, but check the category scores for your use.
- Is Claude Opus 5 better than Claude Sonnet 4.5 for coding?
- Claude Opus 5 scores higher in coding (69 vs 56 on the category index, where 50 is average).
- Which is cheaper, Claude Opus 5 or Claude Sonnet 4.5?
- Claude Sonnet 4.5 is cheaper: $6.00 against $10.00 per million tokens, blended at three input tokens per output token.
- Which is faster, Claude Opus 5 or Claude Sonnet 4.5?
- Claude Opus 5 streams faster: 53 against 40 output tokens per second.
- Which has the larger context window?
- Both accept 1M tokens of context.