BenchLeader

Claude Opus 4.6 vs Claude Opus 5.5

Full profiles: Claude Opus 4.6 (Anthropic) and Claude Opus 5.5 (Anthropic): every benchmark, price and rank.

Updated · Data from 13 sources

As of 9 Nov 2026, Claude Opus 5.5 is ahead of Claude Opus 4.6 on quality (68.9 vs 62.7 on the BenchLeader Index), and Claude Opus 5.5 is 1.3× cheaper at $8.00 vs $10.00 per 1M tokens blended. Claude Opus 5.5 leads in every category we measure both in. Claude Opus 5.5 streams ~2× faster.

Key facts (as of 9 Nov 2026)

  • Claude Opus 4.6 scores 62.7 on the BenchLeader Index and Claude Opus 5.5 scores 68.9 (BenchLeader, 9 Nov 2026).
  • Claude Opus 4.6 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 ~2× faster than Claude Opus 4.6 (Artificial Analysis, 7-day median, 9 Nov 2026).
  • Of the 11 benchmarks both models have, Claude Opus 5.5 leads 11 (BenchLeader, 9 Nov 2026).
  • On Arena WebDev, Claude Opus 4.6 is rated 1547 and Claude Opus 5.5 1818 (LMArena, as published by 9 Nov 2026).

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 casePickWhyConfidence
CodingClaude Opus 5.580 vs 63 category score; Arena WebDev 1818 vs 1547High
MathsClaude Opus 5.574 vs 64 category score; LiveBench Mathematics 97.1% vs 89.3%High
ReasoningClaude Opus 5.572 vs 65 category score; ARC-AGI-2 91.7% vs 69.2%Medium
Images and other mediaClaude Opus 5.570 vs 67 category scoreMedium
Chat quality (human preference)–Only Claude Opus 4.6 has an Arena rating (70 category score)Not comparable
Lowest costClaude Opus 5.5$8.00 vs $10.00 per 1M blended; agentic coding session $0.320 vs $0.400–
Fastest first answerClaude Opus 4.61.1 s (Claude Opus 4.6 (high)) vs 380.6 s (Claude Opus 5.5 (max)) to the first answer token–
High volume on a budgetNeither flagshipA smaller model is usually the better fit: Cheapest good LLMs, Fastest LLMs–

Key differences

  • Claude Opus 5.5 (max) leads on quality: 68.9 vs 62.7.
  • Claude Opus 4.6 (high) is stronger in human preference.
  • Claude Opus 5.5 (max) is stronger in coding, maths, multimodal, reasoning, agents & tools, knowledge, long context.
  • Claude Opus 5.5 (max) is 1.3× cheaper ($8.00 vs $10.00 per 1M blended).
  • Claude Opus 5.5 (max) streams 2.9× faster (115 vs 39 tokens per second).

At a glance

SpecClaude Opus 4.6Claude Opus 5.5
DeveloperAnthropicAnthropic
Released5 Feb 202622 Sep 2026
Context window (tokens)1,000,0001,000,000
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 atClaude Opus 4.6 (high)Claude Opus 5.5 (max)
Open weightsNoNo
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.

CategoryClaude Opus 4.6 (high)Claude Opus 5.5 (max)Leader
Reasoning65.172.3Claude Opus 5.5
Coding62.680.4Claude Opus 5.5
Agents & tools–62.7not comparable
Maths63.774.0Claude Opus 5.5
Knowledge–73.7not comparable
Human preference69.9–not comparable
Multimodal66.770.3Claude Opus 5.5
Long context–67.1not 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.

2550 avg75ReasoningCodingMathsMultimodalClaude Opus 4.6, Reasoning: 65.1Claude Opus 4.6, Coding: 62.6Claude Opus 4.6, Maths: 63.7Claude Opus 4.6, Multimodal: 66.7Claude Opus 5.5, Reasoning: 72.3Claude Opus 5.5, Coding: 80.4Claude Opus 5.5, Maths: 74.0Claude Opus 5.5, Multimodal: 70.3

Not drawn, measured for fewer than two of these models: Agents & tools, Knowledge, Instruction following, Long context, Human preference.

ModelIndex

Where sources disagree

Across the 11 benchmarks both have, Claude Opus 4.6 leads 0, Claude Opus 5.5 leads 11. Every overall index that rates both puts Claude Opus 5.5 ahead.

Overall indexClaude Opus 4.6 (high)Claude Opus 5.5 (max)Leader
BenchLeader Index62.768.9Claude Opus 5.5
Arena Text15031506†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.

MeasureClaude Opus 4.6 (high)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 speed39 tok/s115 tok/s
Time to first answer1.1 s380.6 s
Time to a complete answer–771.1 s

Each model is compared at its best-ranked reasoning-effort setting. Claude Opus 4.6 (high) scores 62.7 and takes 1 s to its first answer token; Claude Opus 4.6 (thinking) scores 62.6 in 1 s, Claude Opus 4.6 scores 62.3 in 1 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

188 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.

MetricPublisherClaude Opus 4.6 (high)Claude Opus 5.5 (max)
BenchLeader IndexBenchLeader62.768.9
Coding scoreBenchLeader62.680.4
Human preference scoreBenchLeader69.9–
Maths scoreBenchLeader63.774.0
Multimodal scoreBenchLeader66.770.3
Reasoning scoreBenchLeader65.172.3
Agents & tools scoreBenchLeader–62.7
Knowledge scoreBenchLeader–73.7
Long context scoreBenchLeader–67.1
Blended price $/MBenchLeader$10.00$8.00
Output speedBenchLeader39 tok/s115 tok/s
Time to first answerBenchLeader1.1 s380.6 s
Context windowBenchLeader1,000,000 tokens1,000,000 tokens
Reasoning
GPQA DiamondEpoch AI Benchmarking Hub90.5%†90.6%
Humanity's Last ExamScale AI / CAIS19.0%†–
SimpleBenchSimpleBench67.6%†–
Arena Hard PromptsArena (LMArena)15301530†
LiveBench 2.0 ReasoningLiveBench–92.2%†
LiveBench 1.0 ReasoningLiveBench88.7%92.2%
GPQA Diamond (AA)Artificial Analysis84.0%†–
Humanity's Last Exam (AA)Artificial Analysis19.1%†61.4%
HLE-Diamond (AA)Artificial Analysis–67.9%
GPQA Diamond (Vals)Vals AI89.7%†–
Kagi LLM BenchmarkKagi LLM Benchmark72.4%†–
ARC-AGI-1ARC Prize94.0%97.5%
ARC-AGI-2ARC Prize69.2%91.7%
ARC-AGI-3ARC Prize0.5%†–
CritPtArtificial Analysis2.8%†31.7%
CritPt v2 hard subset (AA)Artificial Analysis–68.0%
MysteryMechanismVals AI–49.5%†
Chess PuzzlesEpoch AI Benchmarking Hub21.0%†67.0%
Mystery Game PuzzlesEpoch AI Benchmarking Hub15.0%†71.0%
CL-benchEpoch AI Benchmarking Hub20.7%†–
CL-bench LifeEpoch AI Benchmarking Hub17.0%–
LMCAEpoch AI Benchmarking Hub55.8%†68.2%
DTBenchEpoch AI Benchmarking Hub91.2%†98.9%
ForecastBenchForecastBench63.4%†–
Coding
SWE-bench Verified (Epoch)Epoch AI Benchmarking Hub78.7%†–
Show all 188 benchmarks
MetricPublisherClaude Opus 4.6 (high)Claude Opus 5.5 (max)
Coding
SciCodeSciCode–66.9%
WeirdMLWeirdML78.0%–
FrontierCodeCognition26.6%†54.6%†
GSO-BenchGSO-Bench41.2%–
Arena CodingArena (LMArena)15471546†
Arena WebDevArena (LMArena)15471818
LiveBench 2.0 CodingLiveBench–87.1%†
LiveBench 1.0 CodingLiveBench78.2%89.3%
LiveCodeBenchVals AI84.7%†–
IOIVals AI–95.1%†
SWE-bench (Vals)Vals AI78.2%†–
SWE-Bench ProScale AI SEAL51.9%†–
SWE-bench Verified (bash only)SWE-bench75.6%†–
SWE-bench Verified (any scaffold)SWE-bench75.6%†–
Code MigrationVals AI–66.7%†
Code Migration v1.1Vals AI–81.0%†
ProgramBenchVals AI–18.5%†
SWE-bench MultimodalVals AI–70.2%†
Vibe Code Bench 1-100Vals AI–30.4%†
Vibe Code Bench v1.1Vals AI57.6%†90.3%†
SWE-Bench Pro (private)Scale AI SEAL51.9%†–
SWE Atlas: Codebase QnAScale AI SEAL33.3%†–
SWE Atlas: RefactoringScale AI SEAL35.6%†–
SWE Atlas: Test WritingScale AI SEAL36.7%†–
MirrorCodeEpoch AI Benchmarking Hub–78.9%†
CursorBenchCursor–57.8%
ALE-BenchEpoch AI Benchmarking Hub996.5†2147.4†
AlgoTuneAlgoTune1.5–
FrontierSWEEpoch AI Benchmarking Hub–62.3%
Terminal-Bench 4.0 (AA)Artificial Analysis–59.6%
Startrise FrontendStartrise–71.1%†
GameBench 2 OverallDuelLab GameBench 2–87.6†
GameBench 2 by reasoning settingDuelLab GameBench 2–94.8†
Design Arena WebsiteDesign Arena1287†1325†
FrontierCode 1.1 (AA)Artificial Analysis–52.2%
FrontierCode 2.0 (AA)Artificial Analysis–46.4%
Agents & tools
Terminal-BenchTerminal-Bench79.8%†65.8%
CybenchCybench93.0%†–
Remote Labor IndexScale AI / CAIS4.2%†21.3%†
APEX-AgentsMercor46.3%†73.5%
Arena AgentArena (LMArena)–20
LiveBench Long AgenticLiveBench–72.8%†
LiveBench BrowserLiveBench–88.4%†
LiveBench Agentic CodingLiveBench49.0%71.7%
Terminal-Bench HardArtificial Analysis48.5%†–
τ²-Bench Telecom (AA)Artificial Analysis84.8%†–
Terminal-Bench 2.1 (Vals)Vals AI–87.6%†
MCP AtlasScale AI SEAL76.8%†85.4%†
HiL-BenchScale AI SEAL38.3%†59.0%†
τ³-bench Bankingτ²-bench27.3%†–
GDPval-AA v2.1, normalised scoreArtificial Analysis–68.3%
GDPval-AA v2.1Artificial Analysis–1866
ITBench SRE (AA)Artificial Analysis–38.2%
Analyst Agent (AA)Artificial Analysis–56.3%
APEX-Agents (AA)Artificial Analysis33.0%†–
CUA-benchVals AI–14.0%
CyberBenchVals AI–55.4%†
Finance Agent v2Vals AI–58.6%†
Finance Agent v2.1Vals AI–67.8%†
Harvey's Legal Agent Benchmark v1.1Vals AI–9.2%†
Harvey's Legal Agent Benchmark v1Vals AI–3.8%†
Legal Research BenchVals AI–50.5%†
Robo-benchVals AI–14.6%
SREBenchVals AI–33.6%†
Tax Agent BenchVals AI–44.5%†
Terminal-Bench 2.0 (Vals)Vals AI58.4%†–
Terminal-Bench 4.0 (Vals)Vals AI–65.2%†
Terminal-Bench ScienceVals AI–47.1%†
Time Horizon Index: KSPVals AI–91.3%†
Arena SearchArena (LMArena)1222†1214†
DeepResearch BenchDeepResearch Bench55.3%–
METR Time HorizonsMETR78.9%†–
GBAEvalEpoch AI Benchmarking Hub44.1%†–
Vending-Bench 2Andon Labs8017.6†9235.3†
AutomationBenchArtificial Analysis–69.5%
GDP.pdf (AA)Artificial Analysis–26.2%
Harvey LAB-AA v1.1Harvey–4.2%
AA-Briefcase v1.1Artificial Analysis–1800
GDPxGDPx by SemiAnalysis–12.0%
Design Arena AgenticDesign Arena1192†1334†
Terminal-Bench-Science 0.1 (AA)Artificial Analysis–59.0%
CWE-Bench (AA)Artificial Analysis–58.3%
DeepSec-Bench (AA)Artificial Analysis–26.9%
CyberGym end-to-end (AA)Artificial Analysis–0.8%
FACTS SearchGoogle–88.4%†
Maths
FrontierMath Tiers 1–3Epoch AI Benchmarking Hub66.0%†91.2%
FrontierMath Tier 4Epoch AI Benchmarking Hub26.8%†95.0%
OTIS Mock AIMEEpoch AI Benchmarking Hub94.4%†100.0%
ProofBenchVals AI50.0%†100.0%
LiveBench MathematicsLiveBench89.3%97.1%
AIME (Vals)Vals AI95.6%†–
AIME 2026MathArena96.7%–
HMMT February 2026MathArena96.2%–
USAMO 2026MathArena47.0%–
MathArena ApexMathArena34.5%–
Arena MathsArena (LMArena)15161518†
Knowledge
SimpleQA VerifiedEpoch AI Benchmarking Hub47.0%†72.2%
LiveBench 2.0 Data AnalysisLiveBench–80.3%†
LiveBench ResearchLiveBench–88.9%†
LiveBench 1.0 Data AnalysisLiveBench69.9%80.3%
AA-Omniscience v1.1Artificial Analysis–48.1
MMLU-ProVals AI89.1%†–
LegalBenchVals AI85.3%†–
CorpFinVals AI67.0%†–
TaxEvalVals AI76.0%†–
MedQAVals AI95.4%†–
PRBench FinanceScale AI SEAL53.3%†–
PRBench LegalScale AI SEAL52.3%†47.6%†
MultiNRCScale AI SEAL48.3%†–
BioMysteryBenchVals AI–79.3%†
CaseLaw v2Vals AI62.1%†–
ClaimBenchVals AI–100.0%†
Excel Modeling BenchmarkVals AI–75.9%†
Excel Modeling Benchmark v1.1Vals AI–75.8%†
MedCodeVals AI48.2%†49.8%†
MedScribeVals AI86.7%†91.4%†
Public Benefits Bench v1.1Vals AI–70.6%†
DrugDiscoveryBenchScale AI SEAL27.7%†–
EBR-benchEpoch AI Benchmarking Hub12.7%†71.4%
GDP.pdfEpoch AI Benchmarking Hub–30.6%
AA-Omniscience v1.1: accuracyArtificial Analysis–65.5%
AA-Omniscience v1.1: non-hallucinationArtificial Analysis–49.7%
Global-MMLU-Lite (AA)Artificial Analysis92.2%†–
HealthBench Professional (AA)OpenAI–59.9%
Instruction following
LiveBench LanguageLiveBench83.3%86.3%
LiveBench Instruction FollowingLiveBench63.3%65.7%
IFBenchArtificial Analysis44.6%†–
MultiChallengeScale AI SEAL56.0%†–
TutorBenchScale AI SEAL53.5%†–
Arena Instruction FollowingArena (LMArena)15111519†
Human preference
Arena TextArena (LMArena)15031506†
EQ-Bench 4EQ-Bench1210†1340†
Arena Creative WritingArena (LMArena)14981517†
Arena Multi-turnArena (LMArena)15171500†
Arena Longer QueriesArena (LMArena)15221520†
Multimodal
Arena VisionArena (LMArena)13161324†
LiveBench DesignLiveBench–83.3%†
MMMU-ProArtificial Analysis72.5%†87.7%
VISTAScale AI SEAL45.5%†–
MMMU-Pro (Vals)Vals AI83.9%†–
MortgageTaxVals AI68.5%†–
SAGEVals AI–91.3%†
VTBScale AI SEAL27.5%†–
Blueprint-Bench 2Epoch AI Benchmarking Hub–51.2%†
Code2Video-AAArtificial Analysis–1536
AA-3DArtificial Analysis–1202
Long context
AA-LCR v1.1Artificial Analysis67.0%†84.7%
Arena DocumentArena (LMArena)1497–
MLCRArtificial Analysis–27.8%
Composite
Epoch Capabilities IndexEpoch AI Benchmarking Hub156.3†168.4†
LiveBench 2.0LiveBench–83.4%†
LiveBench 1.0LiveBench74.5%83.2%
AA Intelligence Index v5.0Artificial Analysis–59.1
AA Intelligence Index v4.3.2Artificial Analysis26.4†57.6
AA Progress Index v1Artificial Analysis274.5†350
Vals IndexVals AI–70.1†
Vals Finance IndexVals AI–65.3%†
Vals RSI IndexVals AI–37.3%
Vals Science IndexVals AI–58.6%†
Vals Router IndexVals AI–64.2%†
AA Cyber IndexArtificial Analysis–28.7
Safety & honesty
FORTRESSScale AI SEAL20.5%†5.8%
MASKScale AI SEAL96.3%†–

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 5.5 (max): 2 score revisions.
  • Claude Opus 5.5 (max): 1 score revision.
  • Claude Opus 5.5 (max): 1 score revision.
  • Claude Opus 5.5 (max): 2 score revisions.
  • Claude Opus 5.5 (max): 2 score revisions.
  • Claude Opus 5.5 (max): 1 score revision.
  • Claude Opus 5.5 (max): 5 new results (AA Intelligence Index v5.0, AA Progress Index v1, HLE-Diamond (AA)…); 3 score revisions; cost per task moved from $5.98/M to $10.04/M (68% up).
  • Claude Opus 5.5 (max): 1 score revision.
  • Claude Opus 5.5 (max): 2 new results (Robo-bench, Vals RSI Index).
  • Claude Opus 5.5 (max): 2 score revisions.

Rankings: Best LLM overall · Best LLM for coding · Best LLM for agents · Best cheap LLMs

Claude Opus 4.6 vs Claude Opus 5.5: questions

Is Claude Opus 5.5 better than Claude Opus 4.6?
Claude Opus 5.5 (max) leads on quality: 68.9 vs 62.7. The BenchLeader Index combines every independent quality benchmark; Claude Opus 5.5 (max) is ahead overall as of 9 Nov 2026, but check the category scores for your use.
Claude Opus 4.6 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 4.6 or Claude Opus 5.5 better for coding?
Claude Opus 5.5 scores higher in coding (80 vs 63 on the category index, where 50 is average). On Arena WebDev, the top shared coding benchmark, it is 1547 for Claude Opus 4.6 against 1818 for Claude Opus 5.5.
Which is faster, Claude Opus 4.6 or Claude Opus 5.5?
Claude Opus 5.5 streams ~2× faster (115 vs 39 output tokens per second, Artificial Analysis 7-day median).
Which is better for long documents?
Both accept 1,000,000 tokens of context.
More questions (3)
Which has lower latency?
Claude Opus 4.6 answers first: 1.1 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 4.6 vs Claude Opus 5.5?
Across the 11 benchmarks both have, Claude Opus 4.6 leads 0, Claude Opus 5.5 leads 11. 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.