Claude Opus 4.5 vs Claude Sonnet 5.5
Claude Opus 4.5 Verdict
- Claude Sonnet 5.5 (max) leads on quality: 67.6 vs 60.0.
- Claude Opus 4.5 (thinking) is stronger in agents & tools, instruction following, multimodal.
- Claude Sonnet 5.5 (max) is stronger in coding, composite, knowledge, long context, maths, reasoning.
- Claude Sonnet 5.5 (max) is 2.5× cheaper ($4.00 vs $10.00 per 1M blended).
- Claude Sonnet 5.5 (max) streams 3.0× faster (141 vs 48 tokens per second).
| Metric | Claude Opus 4.5 (thinking) | Claude Sonnet 5.5 (max) |
|---|---|---|
| BenchLeader Index | 60.0 | 67.6 |
| Agents & tools score | 74.5 | 69.5 |
| Coding score | 60.6 | 69.8 |
| Composite score | 62.5 | 72.6 |
| Instruction following score | 54.1 | – |
| Knowledge score | 60.2 | 65.4 |
| Long context score | 63.8 | 66.6 |
| Maths score | 64.0 | 72.9 |
| Multimodal score | 57.3 | – |
| Reasoning score | 54.5 | 81.1 |
| Blended price $/M | $10.00 | $4.00 |
| Output speed | 48 tok/s | 141 tok/s |
| Time to first answer | 14.1 s | 487.1 s |
| Context window | 200k | 1M |
| GPQA Diamond | – | 95.6% |
| FrontierMath Tiers 1–3 | – | 88.8% |
| FrontierMath Tier 4 | – | 80.5% |
| OTIS Mock AIME | – | 100.0% |
| SimpleQA Verified | – | 46.5% |
| Terminal-Bench | – | 61.8% |
| SciCode | – | 61.0% |
| APEX-Agents | – | 75.5% |
| ProofBench | – | 100.0% |
| LMArena Agent | – | 12 |
| LiveBench | – | 75.7% |
| LiveBench Reasoning | – | 91.6% |
| LiveBench Coding | – | 91.4% |
| LiveBench Agentic Coding | – | 56.3% |
| LiveBench Mathematics | – | 96.1% |
| LiveBench Data Analysis | – | 59.5% |
| LiveBench Language | – | 78.0% |
| LiveBench Instruction Following | – | 56.8% |
| AA Intelligence Index v4.3.2 | 29.1 | 56 |
| IFBench | 58.0% | – |
| AA-LCR | 77.3% | 82.7% |
| MMMU-Pro | 74.0% | – |
| AA-Omniscience | 14 | 32.3 |
| Terminal-Bench Hard | 47.0% | – |
| GPQA Diamond (AA) | 86.6% | – |
| Humanity's Last Exam (AA) | 30.1% | 55.0% |
| SciCode (AA) | – | 61.0% |
| τ²-Bench Telecom (AA) | 89.5% | – |
| AIME (Vals) | 95.4% | – |
| LiveCodeBench | 83.7% | – |
| MMLU-Pro | 87.3% | – |
| LegalBench | 84.6% | – |
| CorpFin | 65.1% | – |
| TaxEval | 74.9% | – |
| MedQA | 95.9% | – |
| MGSM | 95.2% | – |
| SWE-bench (Vals) | 76.4% | – |
| GPQA Diamond (Vals) | 85.9% | – |
| MultiChallenge | 59.0% | – |
| PRBench Finance | 46.2% | – |
| PRBench Legal | 44.2% | – |
| VISTA | 46.4% | – |
| MultiNRC | 48.6% | – |
| TutorBench | 51.2% | – |
| Kagi LLM Benchmark | 80.2% | – |
| ARC-AGI-1 | 80.0% | – |
| ARC-AGI-2 | 37.6% | – |
| CritPt | 4.6% | 31.4% |
| GDPval-AA v2.1 | – | 67.0% |
| Analyst Agent (AA) | – | 57.5% |
| CaseLaw v2 | 62.6% | – |
| MedCode | 49.2% | – |
| MedScribe | 85.3% | – |
| MMMU-Pro (Vals) | 83.0% | – |
| MortgageTax | 67.7% | – |
| SAGE | 52.1% | – |
| Terminal-Bench 2.0 (Vals) | 53.9% | – |
| Vibe Code Bench v1.1 | 20.6% | – |
| FORTRESS | 9.6% | – |
| MASK | 92.5% | – |
| Mystery Game Puzzles | – | 65.0% |
| CursorBench | – | 55.5% |
| FrontierSWE | – | 61.9% |
| Terminal-Bench 4.0 (AA) | – | 63.6% |
| AutomationBench | – | 71.8% |
| GDP.pdf | – | 25.8% |
| MLCR | – | 75.0% |
| Harvey LAB | – | 2.8% |
| AA-Omniscience: accuracy | 46.6% | 54.0% |
| AA-Omniscience: non-hallucination | 39.0% | 53.0% |
| AA-Briefcase v1.1 | – | 1823 |
| DeepSearchQA | 24.0% | – |
Data as of 2026-10-11. Best configuration of each model; every score links to its source on the model pages.
Claude Opus 4.5 vs Claude Sonnet 5.5: questions
- Is Claude Opus 4.5 better than Claude Sonnet 5.5?
- Claude Sonnet 5.5 (max) leads on quality: 67.6 vs 60.0. The BenchLeader Index combines every independent quality benchmark; Claude Sonnet 5.5 (max) is ahead overall as of 2026-10-11, but check the category scores for your use.
- Is Claude Opus 4.5 better than Claude Sonnet 5.5 for coding?
- Claude Sonnet 5.5 scores higher in coding (70 vs 61 on the category index, where 50 is average).
- Is Claude Opus 4.5 better than Claude Sonnet 5.5 for agentic tasks?
- Claude Opus 4.5 scores higher in agentic tasks (75 vs 70 on the category index, where 50 is average).
- Which is cheaper, Claude Opus 4.5 or Claude Sonnet 5.5?
- Claude Sonnet 5.5 is cheaper: $4.00 against $10.00 per million tokens, blended at three input tokens per output token.
- Which is faster, Claude Opus 4.5 or Claude Sonnet 5.5?
- Claude Sonnet 5.5 streams faster: 141 against 48 output tokens per second.
- Which has the larger context window?
- Claude Sonnet 5.5 accepts more context: 1M against 200k tokens.