Claude Opus 5 vs Claude Opus 5.5
Full profiles: Claude Opus 5 (Anthropic) and Claude Opus 5.5 (Anthropic): every benchmark, price and rank.
Updated · Data from 16 sources
As of 9 Nov 2026, Claude Opus 5 and Claude Opus 5.5 are neck and neck on quality (65.2 vs 68.9 on the BenchLeader Index, inside the ±5.5 margin), and Claude Opus 5.5 is 1.3× cheaper at $8.00 vs $10.00 per 1M tokens blended. Choose Opus 5 for agents & tools (65 vs 63) and fast first answers (2.9 s vs 380.6 s); choose Opus 5.5 for coding (80 vs 68), maths (74 vs 66), and knowledge (74 vs 66), where it also streams ~1.5× faster.
Key facts (as of 9 Nov 2026)
- Claude Opus 5 scores 65.2 on the BenchLeader Index and Claude Opus 5.5 scores 68.9 (BenchLeader, 9 Nov 2026).
- Claude Opus 5 costs $10.00 per 1M tokens blended (list price, 9 Nov 2026).
- Claude Opus 5.5 costs $8.00 per 1M tokens blended (list price, 9 Nov 2026).
- Claude Opus 5.5 streams ~1.5× faster than Claude Opus 5 (Artificial Analysis, 7-day median, 9 Nov 2026).
Claude Opus 5 benchmarks Which to pick for…
The pick's numbers come first. Category scores on the BenchLeader scale (50 is the average model, 15 points one standard deviation). High confidence means a lead of half a standard deviation or more; under one point is called either.
| Use case | Pick | Why | Confidence |
|---|---|---|---|
| Coding | Claude Opus 5.5 | 80 vs 68 category score | High |
| Agents & tool use | Claude Opus 5 | 65 vs 63 category score | Medium |
| Maths | Claude Opus 5.5 | 74 vs 66 category score; OTIS Mock AIME 100.0% vs 97.8% | High |
| Reasoning | Claude Opus 5.5 | 72 vs 71 category score; GPQA Diamond 90.6% vs 92.9% | Medium |
| Knowledge | Claude Opus 5.5 | 74 vs 66 category score | Medium |
| Chat quality (human preference) | – | Only Claude Opus 5 has an Arena rating (76 category score) | Not comparable |
| Lowest cost | Claude Opus 5.5 | $8.00 vs $10.00 per 1M blended; agentic coding session $0.320 vs $0.400 | – |
| Fastest first answer | Claude Opus 5 | 2.9 s (Claude Opus 5) vs 380.6 s (Claude Opus 5.5 (max)) to the first answer token | – |
| High volume on a budget | Neither flagship | A smaller model is usually the better fit: Cheapest good LLMs, Fastest LLMs | – |
Key differences
- Claude Opus 5 and Claude Opus 5.5 (max) are neck and neck on quality (65.2 vs 68.9, within the ±5.5 margin).
- Claude Opus 5 is stronger in agents & tools, human preference.
- Claude Opus 5.5 (max) is stronger in coding, knowledge, maths, reasoning, long context, multimodal.
- Claude Opus 5.5 (max) is 1.3× cheaper ($8.00 vs $10.00 per 1M blended).
- Claude Opus 5.5 (max) streams 1.8× faster (115 vs 64 tokens per second).
At a glance
| Spec | Claude Opus 5 | Claude Opus 5.5 |
|---|---|---|
| Developer | Anthropic | Anthropic |
| Released | 24 Jul 2026 | 22 Sep 2026 |
| Context window (tokens) | 1,000,000 | 1,000,000 |
| Max output (tokens) | – | 128,000 (up to 300K on the Message Batches API (beta)) |
| Input types | – | text, image |
| Reasoning effort settings | – | low, medium, high, xhigh, max |
| Compared at | Claude Opus 5 | Claude Opus 5.5 (max) |
| Open weights | No | No |
| Price in / out / cached input per 1M | $5.00 / $25.00 / $0.500 | $4.00 / $20.00 / $0.200 |
| API model ID | – | claude-opus-5-5 |
| Where to use it | – | Claude API, Amazon Bedrock, Google Cloud, Microsoft Foundry |
Limits, availability and announced prices from the vendors' own pages: platform.claude.com (checked 20 Oct 2026). Everything else is from the day's data.
Category by category
Category scores on the BenchLeader scale: 50 is the average evaluated model, 15 points is one standard deviation. A gap under one point is called level.
| Category | Claude Opus 5 | Claude Opus 5.5 (max) | Leader |
|---|---|---|---|
| Reasoning | 71.2 | 72.3 | Claude Opus 5.5 |
| Coding | 67.9 | 80.4 | Claude Opus 5.5 |
| Agents & tools | 65.1 | 62.7 | Claude Opus 5 |
| Maths | 65.8 | 74.0 | Claude Opus 5.5 |
| Knowledge | 66.3 | 73.7 | Claude Opus 5.5 |
| Human preference | 75.9 | – | not comparable |
| Multimodal | – | 70.3 | not comparable |
| Long context | – | 67.1 | not comparable |
On one chart
Each domain on the index's own scale, where 50 is an average model. Click a domain to see the benchmarks behind it. Pick up to 5 models from the list.
Not drawn, measured for fewer than two of these models: Instruction following, Long context, Multimodal, Human preference.
ModelIndex
Where sources disagree
Across the 4 benchmarks both have, Claude Opus 5 leads 2, Claude Opus 5.5 leads 2. Every overall index that rates both puts Claude Opus 5.5 ahead.
| Overall index | Claude Opus 5 | Claude Opus 5.5 (max) | Leader |
|---|---|---|---|
| BenchLeader Index | 65.2 | 68.9 | neck and neck |
| AA Intelligence Index v5.0 | 44.2† | 59.1 | Claude Opus 5.5 |
| Arena Text | 1490† | 1506 | Claude Opus 5.5 |
Each publisher runs its own tasks, harnesses and effort settings, so their overall verdicts can differ; BenchLeader reconciles them on one scale. † measured at another effort setting of the same model (the publisher did not test the one compared here).
Price, speed and latency
List prices blended at three input tokens per output token. Per-task prices use the token counts on the methodology page. Cost, tokens and time per benchmark task are measured: Artificial Analysis’ averages over its whole Intelligence Index run.
| Measure | Claude Opus 5 | Claude Opus 5.5 (max) |
|---|---|---|
| Blended price per 1M tokens | $10.00 | $8.00 |
| Input / output per 1M | $5.00 / $25.00 | $4.00 / $20.00 |
| Cached input per 1M | $0.500 | $0.200 |
| Price per task: chat reply | $0.0095 | $0.0076 |
| Price per task: summarize a 30-page report | $0.075 | $0.060 |
| Price per task: code edit | $0.068 | $0.054 |
| Price per task: agentic coding session | $0.400 | $0.320 |
| Price per task: structured extraction | $0.015 | $0.012 |
| Agentic coding session, input mostly cached | $0.198 | $0.149 |
| Cost per benchmark task (AA Index) | – | $10.04 |
| Output tokens per task (AA Index) | – | 173k |
| Of which reasoning | – | 120k |
| Time per task (AA Index) | – | 25 min |
| Output speed | 64 tok/s | 115 tok/s |
| Time to first answer | 2.9 s | 380.6 s |
| Time to a complete answer | – | 771.1 s |
Each model is compared at its best-ranked reasoning-effort setting. Claude Opus 5 scores 65.2 and takes 3 s to its first answer token; Claude Opus 5 (max) scores 65.1 in 60 s, Claude Opus 5 (high) scores 64.2 in 14 s. Claude Opus 5.5 (max) scores 68.9 and takes 381 s to its first answer token; Claude Opus 5.5 (xhigh) scores 65.5 in 84 s, Claude Opus 5.5 (high) scores 65.4 in 28 s. Higher effort means more thinking before the answer: better scores, longer waits and more tokens billed. How reasoning effort changes scores and cost.
Every benchmark
163 benchmarks, grouped by category; each name links to the board and its leaders. † measured at another effort setting of the same model, shown for reference and not counted as a win.
| Metric | Publisher | Claude Opus 5 | Claude Opus 5.5 (max) |
|---|---|---|---|
| BenchLeader Index | BenchLeader | 65.2 | 68.9 |
| Agents & tools score | BenchLeader | 65.1 | 62.7 |
| Coding score | BenchLeader | 67.9 | 80.4 |
| Human preference score | BenchLeader | 75.9 | – |
| Knowledge score | BenchLeader | 66.3 | 73.7 |
| Maths score | BenchLeader | 65.8 | 74.0 |
| Reasoning score | BenchLeader | 71.2 | 72.3 |
| Long context score | BenchLeader | – | 67.1 |
| Multimodal score | BenchLeader | – | 70.3 |
| Blended price $/M | BenchLeader | $10.00 | $8.00 |
| Output speed | BenchLeader | 64 tok/s | 115 tok/s |
| Time to first answer | BenchLeader | 2.9 s | 380.6 s |
| Context window | BenchLeader | 1,000,000 tokens | 1,000,000 tokens |
| Reasoning | |||
| GPQA Diamond | Epoch AI Benchmarking Hub | 92.9% | 90.6% |
| SimpleBench | SimpleBench | 80.6% | – |
| Arena Hard Prompts | Arena (LMArena) | 1513† | 1530† |
| LiveBench 2.0 Reasoning | LiveBench | – | 92.2%† |
| LiveBench 1.0 Reasoning | LiveBench | 91.2%† | 92.2% |
| GPQA Diamond (AA) | Artificial Analysis | 93.2%† | – |
| Humanity's Last Exam (AA) | Artificial Analysis | 54.9%† | 61.4% |
| HLE-Diamond (AA) | Artificial Analysis | 44.8%† | 67.9% |
| GPQA Diamond (Vals) | Vals AI | 93.4% | – |
| ARC-AGI-1 | ARC Prize | 97.5%† | 97.5% |
| ARC-AGI-2 | ARC Prize | 90.4%† | 91.7% |
| ARC-AGI-3 | ARC Prize | 30.2%† | – |
| CritPt | Artificial Analysis | 29.1%† | 31.7% |
| CritPt v2 hard subset (AA) | Artificial Analysis | 50.0%† | 68.0% |
| MysteryMechanism | Vals AI | 37.4% | 49.5%† |
| Chess Puzzles | Epoch AI Benchmarking Hub | 43.0%† | 67.0% |
| Mystery Game Puzzles | Epoch AI Benchmarking Hub | 37.0% | 71.0% |
| LMCA | Epoch AI Benchmarking Hub | 63.3%† | 68.2% |
| DTBench | Epoch AI Benchmarking Hub | 97.6%† | 98.9% |
| ForecastBench | ForecastBench | 66.5%† | – |
| BTF-3 | Epoch AI Benchmarking Hub | 12.0%† | – |
| Coding | |||
| SciCode | SciCode | 56.4%† | 66.9% |
| WeirdML | WeirdML | 86.3% | – |
| FrontierCode | Cognition | 53.4%† | 54.6%† |
| Arena Coding | Arena (LMArena) | 1528† | 1546† |
Show all 163 benchmarks
| Metric | Publisher | Claude Opus 5 | Claude Opus 5.5 (max) |
|---|---|---|---|
| Coding | |||
| Arena WebDev | Arena (LMArena) | 1691† | 1818 |
| LiveBench 2.0 Coding | LiveBench | – | 87.1%† |
| LiveBench 1.0 Coding | LiveBench | 81.5%† | 89.3% |
| LiveCodeBench | Vals AI | 89.0% | – |
| IOI | Vals AI | 84.3% | 95.1%† |
| SWE-bench (Vals) | Vals AI | 97.0% | – |
| Code Migration | Vals AI | 57.5% | 66.7%† |
| Code Migration v1.1 | Vals AI | – | 81.0%† |
| ProgramBench | Vals AI | 3.0% | 18.5%† |
| SWE-bench Multimodal | Vals AI | – | 70.2%† |
| Vibe Code Bench 1-100 | Vals AI | 28.5% | 30.4%† |
| Vibe Code Bench v1.1 | Vals AI | 88.4% | 90.3%† |
| SWE Atlas: Codebase QnA | Scale AI SEAL | 63.2%† | – |
| SWE Atlas: Test Writing | Scale AI SEAL | 62.2%† | – |
| MirrorCode | Epoch AI Benchmarking Hub | – | 78.9%† |
| DeepSWE v1.1 | Epoch AI Benchmarking Hub | 73.7%† | – |
| CursorBench | Cursor | 46.6%† | 57.8% |
| ALE-Bench | Epoch AI Benchmarking Hub | 2164.6† | 2147.4† |
| FrontierSWE | Epoch AI Benchmarking Hub | 52.0%† | 62.3% |
| Terminal-Bench 4.0 (AA) | Artificial Analysis | 49.0%† | 59.6% |
| Terminal-Bench 2.1 (AA) | Artificial Analysis | 89.1%† | – |
| Startrise Frontend | Startrise | 82.3% | 71.1%† |
| GameBench 2 Overall | DuelLab GameBench 2 | 76.6 | 87.6† |
| GameBench 2 by reasoning setting | DuelLab GameBench 2 | 84.7† | 94.8† |
| Design Arena Website | Design Arena | 1306 | 1325† |
| FrontierCode 1.1 (AA) | Artificial Analysis | – | 52.2% |
| FrontierCode 2.0 (AA) | Artificial Analysis | 31.1%† | 46.4% |
| Agents & tools | |||
| Terminal-Bench | Terminal-Bench | 52.1%† | 65.8% |
| OSWorld-Verified 2.0 | OSWorld | 31.4%† | – |
| Remote Labor Index | Scale AI / CAIS | – | 21.3%† |
| APEX-Agents | Mercor | 65.8%† | 73.5% |
| Arena Agent | Arena (LMArena) | 7.5† | 20 |
| LiveBench Long Agentic | LiveBench | – | 72.8%† |
| LiveBench Browser | LiveBench | – | 88.4%† |
| LiveBench Agentic Coding | LiveBench | 65.2%† | 71.7% |
| Terminal-Bench 2.1 (Vals) | Vals AI | 84.6% | 87.6%† |
| MCP Atlas | Scale AI SEAL | 85.8%† | 85.4%† |
| HiL-Bench | Scale AI SEAL | 57.0% | 59.0%† |
| τ³-bench Banking | τ²-bench | 48.7%† | – |
| GDPval-AA v2.1, normalised score | Artificial Analysis | – | 68.3% |
| GDPval-AA v2.1 | Artificial Analysis | – | 1866 |
| τ³-Banking (AA) | Artificial Analysis | 42.1%† | – |
| ITBench SRE (AA) | Artificial Analysis | – | 38.2% |
| Analyst Agent (AA) | Artificial Analysis | 53.8%† | 56.3% |
| CUA-bench | Vals AI | 9.0%† | 14.0% |
| CyberBench | Vals AI | 65.4% | 55.4%† |
| Finance Agent v2 | Vals AI | 58.6% | 58.6%† |
| Finance Agent v2.1 | Vals AI | – | 67.8%† |
| Harvey's Legal Agent Benchmark v1.1 | Vals AI | – | 9.2%† |
| Harvey's Legal Agent Benchmark v1 | Vals AI | 6.7% | 3.8%† |
| Legal Research Bench | Vals AI | 55.3% | 50.5%† |
| Robo-bench | Vals AI | – | 14.6% |
| SkillsBench | Vals AI | 60.4% | – |
| SREBench | Vals AI | 12.2% | 33.6%† |
| Tax Agent Bench | Vals AI | 47.1% | 44.5%† |
| Terminal-Bench 4.0 (Vals) | Vals AI | 53.5% | 65.2%† |
| Terminal-Bench Science | Vals AI | 27.1% | 47.1%† |
| Time Horizon Index: KSP | Vals AI | 18.8% | 91.3%† |
| Arena Search | Arena (LMArena) | 1214† | 1214† |
| BALROG | BALROG | 63.4%† | – |
| PostTrainBench | Epoch AI Benchmarking Hub | 35.0% | – |
| GBAEval | Epoch AI Benchmarking Hub | 79.6% | – |
| Vending-Bench 2 | Andon Labs | 11181.9 | 9235.3† |
| AutomationBench | Artificial Analysis | 56.6%† | 69.5% |
| GDP.pdf (AA) | Artificial Analysis | 21.6%† | 26.2% |
| Harvey LAB-AA v1.1 | Harvey | – | 4.2% |
| EnterpriseOps-Gym | Artificial Analysis | 47.5%† | – |
| AA-Briefcase v1.1 | Artificial Analysis | 1655† | 1800 |
| GDPx | GDPx by SemiAnalysis | – | 12.0% |
| Design Arena Agentic | Design Arena | 1266 | 1334† |
| Terminal-Bench-Science 0.1 (AA) | Artificial Analysis | 28.6%† | 59.0% |
| CWE-Bench (AA) | Artificial Analysis | – | 58.3% |
| DeepSec-Bench (AA) | Artificial Analysis | 25.9%† | 26.9% |
| CyberGym end-to-end (AA) | Artificial Analysis | – | 0.8% |
| FACTS Search | – | 88.4%† | |
| Maths | |||
| FrontierMath Tiers 1–3 | Epoch AI Benchmarking Hub | 85.6%† | 91.2% |
| FrontierMath Tier 4 | Epoch AI Benchmarking Hub | 73.2%† | 95.0% |
| OTIS Mock AIME | Epoch AI Benchmarking Hub | 97.8% | 100.0% |
| ProofBench | Vals AI | 99.0%† | 100.0% |
| LiveBench Mathematics | LiveBench | 95.7%† | 97.1% |
| Arena Maths | Arena (LMArena) | 1515† | 1518† |
| Knowledge | |||
| SimpleQA Verified | Epoch AI Benchmarking Hub | 59.9%† | 72.2% |
| LiveBench 2.0 Data Analysis | LiveBench | – | 80.3%† |
| LiveBench Research | LiveBench | – | 88.9%† |
| LiveBench 1.0 Data Analysis | LiveBench | 74.5%† | 80.3% |
| AA-Omniscience v1.1 | Artificial Analysis | 37.6† | 48.1 |
| MMLU-Pro | Vals AI | 91.6% | – |
| LegalBench | Vals AI | 87.0% | – |
| CorpFin | Vals AI | 73.2% | – |
| TaxEval | Vals AI | 75.1% | – |
| PRBench Legal | Scale AI SEAL | – | 47.6%† |
| BioMysteryBench | Vals AI | 79.3% | 79.3%† |
| ClaimBench | Vals AI | – | 100.0%† |
| Excel Modeling Benchmark | Vals AI | 73.6% | 75.9%† |
| Excel Modeling Benchmark v1.1 | Vals AI | – | 75.8%† |
| MedCode | Vals AI | 63.6% | 49.8%† |
| MedScribe | Vals AI | 91.0% | 91.4%† |
| Public Benefits Bench v1.1 | Vals AI | 76.9% | 70.6%† |
| DrugDiscoveryBench | Scale AI SEAL | 53.7%† | – |
| EBR-bench | Epoch AI Benchmarking Hub | 45.7%† | 71.4% |
| GDP.pdf | Epoch AI Benchmarking Hub | 24.0%† | 30.6% |
| AA-Omniscience v1.1: accuracy | Artificial Analysis | 60.9%† | 65.5% |
| AA-Omniscience v1.1: non-hallucination | Artificial Analysis | 40.6%† | 49.7% |
| HealthBench Professional (AA) | OpenAI | – | 59.9% |
| Instruction following | |||
| LiveBench Language | LiveBench | 88.7%† | 86.3% |
| LiveBench Instruction Following | LiveBench | 63.8%† | 65.7% |
| Arena Instruction Following | Arena (LMArena) | 1494† | 1519† |
| Human preference | |||
| Arena Text | Arena (LMArena) | 1489† | 1506† |
| EQ-Bench 4 | EQ-Bench | 1365 | 1340† |
| Arena Creative Writing | Arena (LMArena) | 1473† | 1517† |
| Arena Multi-turn | Arena (LMArena) | 1486† | 1500† |
| Arena Longer Queries | Arena (LMArena) | 1501† | 1520† |
| Multimodal | |||
| Arena Vision | Arena (LMArena) | 1317† | 1324† |
| LiveBench Design | LiveBench | – | 83.3%† |
| MMMU-Pro | Artificial Analysis | 84.7%† | 87.7% |
| MMMU-Pro (Vals) | Vals AI | 89.9% | – |
| MortgageTax | Vals AI | 72.1% | – |
| SAGE | Vals AI | – | 91.3%† |
| Blueprint-Bench 2 | Epoch AI Benchmarking Hub | 30.4% | 51.2%† |
| Code2Video-AA | Artificial Analysis | – | 1536 |
| AA-3D | Artificial Analysis | – | 1202 |
| Long context | |||
| AA-LCR v1.1 | Artificial Analysis | 79.3%† | 84.7% |
| Arena Document | Arena (LMArena) | 1486† | – |
| MLCR | Artificial Analysis | 11.1%† | 27.8% |
| Composite | |||
| Epoch Capabilities Index | Epoch AI Benchmarking Hub | 164.4 | 168.4† |
| LiveBench 2.0 | LiveBench | – | 83.4%† |
| LiveBench 1.0 | LiveBench | 80.1%† | 83.2% |
| AA Intelligence Index v5.0 | Artificial Analysis | 44.2† | 59.1 |
| AA Intelligence Index v4.3.2 | Artificial Analysis | 50.8† | 57.6 |
| AA Progress Index v1 | Artificial Analysis | 333.7† | 350 |
| Vals Index | Vals AI | – | 70.1† |
| Vals Finance Index | Vals AI | – | 65.3%† |
| Vals RSI Index | Vals AI | 33.0%† | 37.3% |
| Vals Science Index | Vals AI | 47.9% | 58.6%† |
| Vals Multimodal Index | Vals AI | 73.9% | – |
| Vals Router Index | Vals AI | – | 64.2%† |
| AA Cyber Index | Artificial Analysis | – | 28.7 |
| Safety & honesty | |||
| FORTRESS | Scale AI SEAL | 16.8% | 5.8% |
Data as of 2026-11-09. Best configuration of each model; every score links to its source on the model pages.
DuelLab GameBench 2, release gb2-20261103-eaea31df94e6 (https://benchmarks.duellab.org/releases/gb2-20261103-eaea31df94e6/), CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Scores mapped to BenchLeader model names; not endorsed by DuelLab.
What changed
- Claude Opus 5: 1 score revision.
- Claude Opus 5.5 (max): 2 score revisions.
- Claude Opus 5.5 (max): 1 score revision.
- Claude Opus 5.5 (max): 1 score revision.
- Claude Opus 5: 1 score revision.
- Claude Opus 5.5 (max): 2 score revisions.
- Claude Opus 5.5 (max): 2 score revisions.
- Claude Opus 5: 1 score revision.
- Claude Opus 5.5 (max): 1 score revision.
- Claude Opus 5: 1 score revision.
Related comparisons
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- Claude Opus 5 vs GPT-6 Astra
- Claude Opus 5.5 vs Claude Fable 5.2
- Claude Opus 5.5 vs Gemini 4 Carbon
- Claude Opus 5.5 vs GPT-6 Astra
- Claude Opus 5.5 vs GPT-6.1 Sol
- Claude Sonnet 5 vs Claude Opus 5.5
Rankings: Best LLM overall · Best LLM for coding · Best LLM for agents · Best cheap LLMs
Claude Opus 5 vs Claude Opus 5.5: questions
- Is Claude Opus 5 better than Claude Opus 5.5?
- Claude Opus 5 and Claude Opus 5.5 (max) are neck and neck on quality (65.2 vs 68.9, within the ±5.5 margin). The BenchLeader Index combines every independent quality benchmark; the two are within the margin of error as of 9 Nov 2026, so check the category scores for your use.
- Claude Opus 5 vs Claude Opus 5.5: which is cheaper, and will that change?
- Claude Opus 5.5 is cheaper today: $8.00 against $10.00 per million tokens, blended at three input tokens per output token. No price change has been announced for either.
- Is Claude Opus 5 or Claude Opus 5.5 better for coding?
- Claude Opus 5.5 scores higher in coding (80 vs 68 on the category index, where 50 is average).
- Which is faster, Claude Opus 5 or Claude Opus 5.5?
- Claude Opus 5.5 streams ~1.5× faster (115 vs 64 output tokens per second, Artificial Analysis 7-day median).
- Is Claude Opus 5 or Claude Opus 5.5 better for agents and tool use?
- Claude Opus 5 scores higher in agentic tasks (65 vs 63 on the category index, where 50 is average).
More questions (4)
- Which is better for long documents?
- Both accept 1,000,000 tokens of context.
- Which has lower latency?
- Claude Opus 5 answers first: 2.9 s against 380.6 s to the first answer token, as Artificial Analysis measures it. Reasoning effort drives most of this: a higher setting thinks longer before it answers.
- Do independent benchmarks agree on Claude Opus 5 vs Claude Opus 5.5?
- Across the 4 benchmarks both have, Claude Opus 5 leads 2, Claude Opus 5.5 leads 2. Every overall index that rates both puts Claude Opus 5.5 ahead.
- When was Claude Opus 5.5 released?
- Claude Opus 5.5 was released on 22 Sep 2026.