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Claude Opus 5 vs Gemini 3.5 Flash

Full profiles: Claude Opus 5 (Anthropic) and Gemini 3.5 Flash (Google): every benchmark, price and rank.

Updated · Data from 11 sources

As of 25 Oct 2026, Claude Opus 5 (max) leads on quality (68.8 vs 63.1 on the BenchLeader Index), but Gemini 3.5 Flash (high) costs 3.0× less, so it is the better buy unless you need the extra quality. Claude Opus 5 leads in every category we measure both in.

Claude Opus 5 benchmarks max Anthropic Gemini 3.5 Flash benchmarks high GoogleOpen in the comparison tool

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 570 vs 60 category score; Arena WebDev 1691 vs 1499High
Agents & tool useEither64 vs 63 category score; τ³-Banking (AA) 42.1% vs 32.2%Either
MathsClaude Opus 571 vs 58 category score; FrontierMath Tiers 1–3 85.6% vs 62.8%High
ReasoningClaude Opus 574 vs 61 category score; GPQA Diamond 93.9% vs 92.8%High
KnowledgeClaude Opus 572 vs 65 category score; AA-Omniscience 37.1 vs 21.2Medium
Long documentsClaude Opus 565 vs 62 category score; AA-LCR 79.3% vs 73.3%Medium
Images and other mediaClaude Opus 568 vs 67 category score; MMMU-Pro 84.7% vs 84.3%Medium
Chat quality (human preference)Claude Opus 569 vs 67 on Arena votesMedium
Lowest costGemini 3.5 Flash$3.38 vs $10.00 per 1M blended; agentic coding session $0.126 vs $0.400–
Fastest first answerGemini 3.5 Flash14.2 s (Gemini 3.5 Flash (high)) vs 24.1 s (Claude Opus 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 (max) leads on quality: 68.8 vs 63.1.
  • Claude Opus 5 (max) is stronger in agents & tools, coding, composite, human preference, knowledge, long context, maths, multimodal, reasoning.
  • Gemini 3.5 Flash (high) is stronger in instruction following.
  • Gemini 3.5 Flash (high) is 3.0× cheaper ($3.38 vs $10.00 per 1M blended).
  • Gemini 3.5 Flash (high) streams 3.9× faster (222 vs 57 tokens per second).

At a glance

SpecClaude Opus 5Gemini 3.5 Flash
DeveloperAnthropicGoogle
Released24 Jul 202619 May 2026
Context window (tokens)1,000,0001,048,576
Compared atClaude Opus 5 (max)Gemini 3.5 Flash (high)
Open weightsNoNo
Price in / out / cached input per 1M$5.00 / $25.00 / $0.500$1.50 / $9.00 / $0.150

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 5 (max)Gemini 3.5 Flash (high)Leader
Reasoning74.161.3Claude Opus 5
Coding70.259.8Claude Opus 5
Agents & tools64.363.4level
Maths70.658.3Claude Opus 5
Knowledge71.665.2Claude Opus 5
Instruction following–74.3not comparable
Human preference68.566.8Claude Opus 5
Multimodal67.966.6Claude Opus 5
Long context64.761.6Claude Opus 5
Composite86.365.9Claude Opus 5

Where sources disagree

Across the 50 benchmarks both have, Claude Opus 5 leads 46, Gemini 3.5 Flash leads 4. Every overall index that rates both puts Claude Opus 5 ahead.

Overall indexClaude Opus 5 (max)Gemini 3.5 Flash (high)Leader
BenchLeader Index68.863.1Claude Opus 5
AA Intelligence Index v4.3.250.832.6Claude Opus 5
Arena Text14911477Claude Opus 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; suite cost is what Artificial Analysis paid to run its whole Intelligence Index.

MeasureClaude Opus 5 (max)Gemini 3.5 Flash (high)
Blended price per 1M tokens$10.00$3.38
Input / output per 1M$5.00 / $25.00$1.50 / $9.00
Cached input per 1M$0.500$0.150
Price per task: chat reply$0.0095$0.0033
Price per task: summarize a 30-page report$0.075$0.023
Price per task: code edit$0.068$0.022
Price per task: agentic coding session$0.400$0.126
Price per task: structured extraction$0.015$0.0048
Cost to run a full benchmark suite$5.86$3.69
Output speed57 tok/s222 tok/s
Time to first answer24.1 s14.2 s
Time to a complete answer32.9 s16.4 s

Per token is not per task: on Artificial Analysis' full suite Claude Opus 5 (max) cost $5.86 and Gemini 3.5 Flash (high) $3.69, because Gemini 3.5 Flash (high) used about 1.9× as many tokens for the same work, which a per-token price hides.

Each model is compared at its best-ranked reasoning-effort setting. Claude Opus 5 (max) scores 68.8 and takes 24 s to its first answer token; Claude Opus 5 (high) scores 67.9 in 10 s, Claude Opus 5 (xhigh) scores 67.4 in 25 s. Gemini 3.5 Flash (high) scores 63.1 and takes 14 s to its first answer token; Gemini 3.5 Flash (medium) scores 62.8 in 12 s, Gemini 3.5 Flash (minimal) scores 56.4 in 1 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

142 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 5 (max)Gemini 3.5 Flash (high)
BenchLeader IndexBenchLeader68.863.1
Agents & tools scoreBenchLeader64.363.4
Coding scoreBenchLeader70.259.8
Composite scoreBenchLeader86.365.9
Human preference scoreBenchLeader68.566.8
Knowledge scoreBenchLeader71.665.2
Long context scoreBenchLeader64.761.6
Maths scoreBenchLeader70.658.3
Multimodal scoreBenchLeader67.966.6
Reasoning scoreBenchLeader74.161.3
Instruction following scoreBenchLeader–74.3
Blended price $/MBenchLeader$10.00$3.38
Output speedBenchLeader57 tok/s222 tok/s
Time to first answerBenchLeader24.1 s14.2 s
Context windowBenchLeader1,000,000 tokens1,048,576 tokens
Reasoning
GPQA DiamondEpoch AI Benchmarking Hub93.9%92.8%
SimpleBenchSimpleBench80.6%†76.7%†
Arena Hard PromptsArena (LMArena)15151495
LiveBench 2.0 ReasoningLiveBench91.2%†–
LiveBench 1.0 ReasoningLiveBench91.2%82.0%
GPQA Diamond (AA)Artificial Analysis93.2%92.2%
Humanity's Last Exam (AA)Artificial Analysis54.9%42.7%
GPQA Diamond (Vals)Vals AI93.4%†92.7%
EnigmaEvalScale AI SEAL–25.4%
ARC-AGI-1ARC Prize97.5%92.5%
ARC-AGI-2ARC Prize90.4%72.1%
ARC-AGI-3ARC Prize30.2%†–
CritPtArtificial Analysis29.1%13.1%
MysteryMechanismVals AI37.4%†–
Chess PuzzlesEpoch AI Benchmarking Hub43.0%45.0%
Mystery Game PuzzlesEpoch AI Benchmarking Hub59.0%32.0%
LMCAEpoch AI Benchmarking Hub63.3%47.1%
DTBenchEpoch AI Benchmarking Hub97.6%94.7%
ForecastBenchForecastBench66.5%64.3%†
BTF-3Epoch AI Benchmarking Hub12.0%†–
Coding
SWE-bench Verified (Epoch)Epoch AI Benchmarking Hub–79.3%
SciCodeSciCode56.4%53.9%
WeirdMLWeirdML91.8%62.6%
FrontierCodeCognition53.4%–
Arena CodingArena (LMArena)15281508
Show all 142 benchmarks
MetricPublisherClaude Opus 5 (max)Gemini 3.5 Flash (high)
Coding
Arena WebDevArena (LMArena)16911499
LiveBench 2.0 CodingLiveBench90.8%†–
LiveBench 1.0 CodingLiveBench81.5%78.2%
LiveCodeBenchVals AI89.0%†87.6%
IOIVals AI84.3%†–
SWE-bench (Vals)Vals AI97.0%†78.8%
Code MigrationVals AI57.5%†26.8%
ProgramBenchVals AI3.0%†0.0%
Vibe Code Bench 1-100Vals AI28.5%†–
Vibe Code Bench v1.1Vals AI88.4%†48.7%
SWE Atlas: Codebase QnAScale AI SEAL63.2%†–
SWE Atlas: Test WritingScale AI SEAL62.2%†–
Surface Evolver BenchEpoch AI Benchmarking Hub–58.1%†
DeepSWE v1.1Epoch AI Benchmarking Hub73.7%36.1%
CursorBenchCursor46.6%–
ALE-BenchEpoch AI Benchmarking Hub2164.6†911.0
FrontierSWEEpoch AI Benchmarking Hub52.0%–
Terminal-Bench 4.0 (AA)Artificial Analysis49.0%6.6%
Terminal-Bench 2.1 (AA)Artificial Analysis89.1%78.7%
Startrise FrontendStartrise82.3%†–
Agents & tools
Terminal-BenchTerminal-Bench51.8%–
OSWorld-Verified 2.0OSWorld31.4%–
APEX-AgentsMercor65.8%27.5%†
Arena AgentArena (LMArena)8.2–
LiveBench Long AgenticLiveBench62.1%†–
LiveBench BrowserLiveBench84.0%†–
LiveBench Agentic CodingLiveBench65.2%49.0%
Terminal-Bench HardArtificial Analysis–40.9%
τ²-Bench Telecom (AA)Artificial Analysis–95.3%
Terminal-Bench 2.1 (Vals)Vals AI84.6%†74.2%
MCP AtlasScale AI SEAL85.8%†83.6%
HiL-BenchScale AI SEAL57.0%†27.7%†
τ³-bench Bankingτ²-bench48.7%–
τ³-Banking (AA)Artificial Analysis42.1%32.2%
ITBench SRE (AA)Artificial Analysis–40.4%
Analyst Agent (AA)Artificial Analysis53.8%45.0%
APEX-Agents (AA)Artificial Analysis–47.0%
CUA-benchVals AI9.0%–
CyberBenchVals AI65.4%†–
Finance Agent v2Vals AI58.6%†57.9%
Harvey's Legal Agent Benchmark v1Vals AI6.7%†2.5%
Legal Research BenchVals AI55.3%†30.8%
SkillsBenchVals AI60.4%†52.7%
SREBenchVals AI12.2%†–
Tax Agent BenchVals AI45.5%†21.6%
Terminal-Bench 2.0 (Vals)Vals AI–67.4%
Terminal-Bench 4.0 (Vals)Vals AI53.5%†6.1%
Terminal-Bench ScienceVals AI27.1%†5.7%
Time Horizon Index: KSPVals AI18.8%†–
Web Search IndexVals AI–37.0%
Arena SearchArena (LMArena)1214†–
BALROGBALROG63.4%–
PostTrainBenchEpoch AI Benchmarking Hub35.0%†–
GBAEvalEpoch AI Benchmarking Hub79.6%†6.7%†
Vending-Bench 2Andon Labs11181.9†5396.4†
AutomationBenchArtificial Analysis56.6%42.1%
GDP.pdf (AA)Artificial Analysis21.6%19.8%
EnterpriseOps-GymArtificial Analysis47.5%50.1%
AA-Briefcase v1.1Artificial Analysis1657874
Terminal-Bench-Science 0.1 (AA)Artificial Analysis28.6%–
DeepSec-Bench (AA)Artificial Analysis25.9%–
FACTS SearchGoogle85.3%†64.3%†
Maths
FrontierMath Tiers 1–3Epoch AI Benchmarking Hub85.6%62.8%
FrontierMath Tier 4Epoch AI Benchmarking Hub73.2%26.8%
OTIS Mock AIMEEpoch AI Benchmarking Hub98.9%95.6%
ProofBenchVals AI99.0%31.0%
LiveBench MathematicsLiveBench95.7%88.2%
AIME 2026MathArena–95.0%†
HMMT February 2026MathArena–95.5%†
MathArena ApexMathArena–32.3%†
Arena MathsArena (LMArena)15171497
Knowledge
SimpleQA VerifiedEpoch AI Benchmarking Hub59.9%66.2%
LiveBench 2.0 Data AnalysisLiveBench74.6%†–
LiveBench ResearchLiveBench88.9%†–
LiveBench 1.0 Data AnalysisLiveBench74.5%64.9%
AA-OmniscienceArtificial Analysis37.121.2
MMLU-ProVals AI91.6%†89.5%
LegalBenchVals AI87.0%†83.6%
CorpFinVals AI73.2%†64.7%
TaxEvalVals AI75.1%†74.4%
BioMysteryBenchVals AI79.3%†–
Excel Modeling BenchmarkVals AI73.6%†63.5%
MedCodeVals AI63.6%†55.8%
MedScribeVals AI91.0%†76.6%
Public Benefits Bench v1.1Vals AI76.9%†59.5%
DrugDiscoveryBenchScale AI SEAL53.7%50.0%
EBR-benchEpoch AI Benchmarking Hub45.7%4.8%
GDP.pdfEpoch AI Benchmarking Hub24.0%14.0%†
AA-Omniscience: accuracyArtificial Analysis60.9%51.4%
AA-Omniscience: non-hallucinationArtificial Analysis39.2%37.8%
Instruction following
LiveBench LanguageLiveBench88.7%84.6%
LiveBench Instruction FollowingLiveBench63.8%75.6%
IFBenchArtificial Analysis–76.3%
Arena Instruction FollowingArena (LMArena)14951465
Human preference
Arena TextArena (LMArena)14911477
EQ-Bench 4EQ-Bench1360†1081†
Arena Creative WritingArena (LMArena)14741464
Arena Multi-turnArena (LMArena)14871480
Arena Longer QueriesArena (LMArena)15031482
Multimodal
Arena VisionArena (LMArena)1320†1308
LiveBench DesignLiveBench83.0%†–
MMMU-ProArtificial Analysis84.7%84.3%
MMMU-Pro (Vals)Vals AI89.9%†88.3%
MortgageTaxVals AI72.1%†68.1%
SAGEVals AI49.4%†49.9%
Blueprint-Bench 2Epoch AI Benchmarking Hub30.4%†33.6%†
Long context
AA-LCRArtificial Analysis79.3%73.3%
Arena DocumentArena (LMArena)1490†1453
MLCRArtificial Analysis11.1%10.0%
Composite
Epoch Capabilities IndexEpoch AI Benchmarking Hub163.9†154.9†
LiveBench 2.0LiveBench82.1%†–
LiveBench 1.0LiveBench80.1%74.6%
AA Intelligence Index v4.3.2Artificial Analysis50.832.6
Vals RSI IndexVals AI33.0%–
Vals Science IndexVals AI47.9%†–
Vals Multimodal IndexVals AI73.9%†62.9%
Safety & honesty
FORTRESSScale AI SEAL16.8%†–

Data as of 2026-10-25. Best configuration of each model; every score links to its source on the model pages.

What changed

  • Claude Opus 5 (max): 1 new result (Vals RSI Index).
  • Gemini 3.5 Flash (high): 1 new result (Harvey's Legal Agent Benchmark v1).
  • Claude Opus 5 (max): 1 score revision.
  • Gemini 3.5 Flash (high): 1 score revision.
  • Claude Opus 5 (max): 1 new result (ForecastBench); 1 score revision.
  • Claude Opus 5 (max): BenchLeader Index 68.3 → 68.9.
  • Gemini 3.5 Flash (high): BenchLeader Index 62.5 → 63.2.
  • Claude Opus 5 (max): 4 new results (GDPval-AA v2.1, AA-Omniscience: accuracy, AA-Omniscience: non-hallucination…).
  • Gemini 3.5 Flash (high): 3 new results (GDPval-AA v2.1, AA-Omniscience: accuracy, AA-Omniscience: non-hallucination).
  • Claude Opus 5 (max): 1 score revision.

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

Claude Opus 5 vs Gemini 3.5 Flash: questions

Is Claude Opus 5 better than Gemini 3.5 Flash?
Claude Opus 5 (max) leads on quality: 68.8 vs 63.1. The BenchLeader Index combines every independent quality benchmark; Claude Opus 5 (max) is ahead overall as of 2026-10-25, but check the category scores for your use.
Which is cheaper, Claude Opus 5 or Gemini 3.5 Flash, and will that change?
Gemini 3.5 Flash is cheaper today: $3.38 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 better than Gemini 3.5 Flash for coding?
Claude Opus 5 scores higher in coding (70 vs 60 on the category index, where 50 is average). On Arena WebDev, the top shared coding benchmark, it is 1691 for Claude Opus 5 against 1499 for Gemini 3.5 Flash.
Is Claude Opus 5 better than Gemini 3.5 Flash for agents and tool use?
They are level in agentic tasks (64 vs 63 on the category index). On τ³-Banking (AA), the top shared agents & tools benchmark, it is 42.1% for Claude Opus 5 against 32.2% for Gemini 3.5 Flash.
Which is better for long documents?
Claude Opus 5 scores higher on long-context benchmarks (65 vs 62). Both take about 1M tokens: Claude Opus 5 1,000,000, Gemini 3.5 Flash 1,048,576.
Which has lower latency?
Gemini 3.5 Flash (high) answers first: 14.2 s against 24.1 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.
Which is faster, Claude Opus 5 or Gemini 3.5 Flash?
Gemini 3.5 Flash streams faster: 222 against 57 output tokens per second.
Do independent benchmarks agree on Claude Opus 5 vs Gemini 3.5 Flash?
Across the 50 benchmarks both have, Claude Opus 5 leads 46, Gemini 3.5 Flash leads 4. Every overall index that rates both puts Claude Opus 5 ahead.
When was Claude Opus 5 released?
Claude Opus 5 was released on 24 Jul 2026.