BenchLeader

Claude Opus 5 vs DeepSeek V4.1 Flash 1017

Full profiles: Claude Opus 5 (Anthropic) and DeepSeek V4.1 Flash 1017 (DeepSeek): every benchmark, price and rank.

Updated · Data from 11 sources

As of 24 Oct 2026, Claude Opus 5 (max) leads on quality (68.8 vs 64.0 on the BenchLeader Index), but DeepSeek V4.1 Flash 1017 (max) costs 19× less, so it is the better buy unless you need the extra quality. Pick Claude Opus 5 for knowledge (72 vs 57); pick DeepSeek V4.1 Flash 1017 for long context (66 vs 65).

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
CodingEither70 vs 70 category score; Arena WebDev 1690 vs 1664Either
Agents & tool useClaude Opus 564 vs 63 category score; DeepSec-Bench (AA) 25.9% vs 24.9%Medium
MathsClaude Opus 571 vs 62 category score; FrontierMath Tiers 1–3 85.6% vs 71.2%High
ReasoningClaude Opus 574 vs 71 category score; GPQA Diamond 93.9% vs 93.2%Medium
KnowledgeClaude Opus 572 vs 57 category score; SimpleQA Verified 59.9% vs 42.5%High
Long documentsDeepSeek V4.1 Flash 101766 vs 65 category score; AA-LCR 82.7% vs 79.3%Medium
Images and other mediaClaude Opus 568 vs 64 category score; MMMU-Pro 84.7% vs 80.6%Medium
Chat quality (human preference)–Only Claude Opus 5 has an Arena rating (69 category score)Not comparable
Lowest costDeepSeek V4.1 Flash 1017$0.525 vs $10.00 per 1M blended; agentic coding session $0.023 vs $0.400–
Fastest first answerDeepSeek V4.1 Flash 101711.2 s (DeepSeek V4.1 Flash 1017 (max)) vs 20.2 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 64.0.
  • Claude Opus 5 (max) is stronger in agents & tools, coding, composite, human preference, knowledge, maths, multimodal, reasoning.
  • DeepSeek V4.1 Flash 1017 (max) is stronger in long context.
  • DeepSeek V4.1 Flash 1017 (max) is 19× cheaper ($0.525 vs $10.00 per 1M blended).
  • DeepSeek V4.1 Flash 1017 (max) streams 3.5× faster (198 vs 57 tokens per second).

At a glance

SpecClaude Opus 5DeepSeek V4.1 Flash 1017
DeveloperAnthropicDeepSeek
Released24 Jul 202617 Oct 2026
Context window (tokens)1,000,0001,048,576
Compared atClaude Opus 5 (max)DeepSeek V4.1 Flash 1017 (max)
Open weightsNoYes
Price in / out / cached input per 1M$5.00 / $25.00 / $0.500$0.300 / $1.20 / $0.0060

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)DeepSeek V4.1 Flash 1017 (max)Leader
Reasoning74.170.6Claude Opus 5
Coding70.270.1level
Agents & tools64.163.0Claude Opus 5
Maths70.661.8Claude Opus 5
Knowledge71.657.1Claude Opus 5
Human preference68.5–not comparable
Multimodal67.963.7Claude Opus 5
Long context64.766.4DeepSeek V4.1 Flash 1017
Composite86.380.0Claude Opus 5

Where sources disagree

Across the 25 benchmarks both have, Claude Opus 5 leads 20, DeepSeek V4.1 Flash 1017 leads 5. Every overall index that rates both puts Claude Opus 5 ahead.

Overall indexClaude Opus 5 (max)DeepSeek V4.1 Flash 1017 (max)Leader
BenchLeader Index68.864.0Claude Opus 5
AA Intelligence Index v4.3.250.845.1Claude 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)DeepSeek V4.1 Flash 1017 (max)
Blended price per 1M tokens$10.00$0.525
Input / output per 1M$5.00 / $25.00$0.300 / $1.20
Cached input per 1M$0.500$0.0060
Price per task: chat reply$0.0095$0.0005
Price per task: summarize a 30-page report$0.075$0.0043
Price per task: code edit$0.068$0.0036
Price per task: agentic coding session$0.400$0.023
Price per task: structured extraction$0.015$0.0008
Cost to run a full benchmark suite$5.86$0.262
Output speed57 tok/s198 tok/s
Time to first answer20.2 s11.2 s
Time to a complete answer29.1 s13.7 s

Per token is not per task: on Artificial Analysis' full suite Claude Opus 5 (max) cost $5.86 and DeepSeek V4.1 Flash 1017 (max) $0.262, because Claude Opus 5 (max) used about 1.2× as many tokens for the same work.

Each model is compared at its best-ranked reasoning-effort setting. Claude Opus 5 (max) scores 68.8 and takes 20 s to its first answer token; Claude Opus 5 (high) scores 67.9 in 9 s, Claude Opus 5 (xhigh) scores 67.4 in 24 s. DeepSeek V4.1 Flash 1017 (max) scores 64.0 and takes 11 s to its first answer token. 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

143 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)DeepSeek V4.1 Flash 1017 (max)
BenchLeader IndexBenchLeader68.864.0
Agents & tools scoreBenchLeader64.163.0
Coding scoreBenchLeader70.270.1
Composite scoreBenchLeader86.380.0
Human preference scoreBenchLeader68.5–
Knowledge scoreBenchLeader71.657.1
Long context scoreBenchLeader64.766.4
Maths scoreBenchLeader70.661.8
Multimodal scoreBenchLeader67.963.7
Reasoning scoreBenchLeader74.170.6
Blended price $/MBenchLeader$10.00$0.525
Output speedBenchLeader57 tok/s198 tok/s
Time to first answerBenchLeader20.2 s11.2 s
Context windowBenchLeader1,000,000 tokens1,048,576 tokens
Reasoning
GPQA DiamondEpoch AI Benchmarking Hub93.9%93.2%
SimpleBenchSimpleBench80.6%†–
Arena Hard PromptsArena (LMArena)1515–
LiveBench 2.0 ReasoningLiveBench91.2%†89.1%†
LiveBench 1.0 ReasoningLiveBench91.2%–
GPQA Diamond (AA)Artificial Analysis93.2%–
Humanity's Last Exam (AA)Artificial Analysis54.9%43.3%
GPQA Diamond (Vals)Vals AI93.4%†–
ARC-AGI-1ARC Prize97.5%93.5%
ARC-AGI-2ARC Prize90.4%78.1%
ARC-AGI-3ARC Prize30.2%†–
CritPtArtificial Analysis29.1%24.0%
MysteryMechanismVals AI37.4%†–
Chess PuzzlesEpoch AI Benchmarking Hub43.0%46.0%
Mystery Game PuzzlesEpoch AI Benchmarking Hub59.0%49.0%
LMCAEpoch AI Benchmarking Hub63.3%–
DTBenchEpoch AI Benchmarking Hub97.6%–
ForecastBenchForecastBench66.5%–
BTF-3Epoch AI Benchmarking Hub12.0%†–
Coding
SciCodeSciCode56.4%–
WeirdMLWeirdML91.8%–
FrontierCodeCognition53.4%–
Arena CodingArena (LMArena)1528–
Arena WebDevArena (LMArena)16901664
LiveBench 2.0 CodingLiveBench90.8%†96.0%†
Show all 143 benchmarks
MetricPublisherClaude Opus 5 (max)DeepSeek V4.1 Flash 1017 (max)
Coding
LiveBench 1.0 CodingLiveBench81.5%–
SciCode (AA)Artificial Analysis56.4%55.9%
LiveCodeBenchVals AI89.0%†–
IOIVals AI84.3%†–
SWE-bench (Vals)Vals AI97.0%†–
Code MigrationVals AI57.5%†44.2%
Code Migration v1.1Vals AI–67.5%
ProgramBenchVals AI3.0%†–
Vibe Code Bench 1-100Vals AI28.5%†–
Vibe Code Bench v1.1Vals AI88.4%†87.7%
SWE Atlas: Codebase QnAScale AI SEAL63.2%†–
SWE Atlas: Test WritingScale AI SEAL62.2%†–
DeepSWE v1.1Epoch AI Benchmarking Hub73.7%–
CursorBenchCursor46.6%–
ALE-BenchEpoch AI Benchmarking Hub2164.6†–
FrontierSWEEpoch AI Benchmarking Hub52.0%–
Terminal-Bench 4.0 (AA)Artificial Analysis49.0%33.8%
Terminal-Bench 2.1 (AA)Artificial Analysis89.1%–
Startrise FrontendStartrise82.3%†–
FrontierCode 1.1 (AA)Artificial Analysis–43.7%
Agents & tools
Terminal-BenchTerminal-Bench51.8%–
OSWorld-Verified 2.0OSWorld31.4%–
APEX-AgentsMercor65.8%–
Arena AgentArena (LMArena)8.1–
LiveBench Long AgenticLiveBench62.1%†50.9%†
LiveBench BrowserLiveBench84.0%†76.0%†
LiveBench Agentic CodingLiveBench65.2%–
Terminal-Bench 2.1 (Vals)Vals AI84.6%†–
MCP AtlasScale AI SEAL85.8%†–
HiL-BenchScale AI SEAL57.0%†–
τ³-bench Bankingτ²-bench48.7%–
GDPval-AA v2.1Artificial Analysis–62.3%
τ³-Banking (AA)Artificial Analysis42.1%–
Analyst Agent (AA)Artificial Analysis53.8%–
CUA-benchVals AI9.0%–
CyberBenchVals AI65.4%†–
Finance Agent v2Vals AI58.6%†57.0%
Finance Agent v2.1Vals AI–62.9%
Harvey's Legal Agent Benchmark v1.1Vals AI–14.2%
Harvey's Legal Agent Benchmark v1Vals AI6.7%†9.2%
Legal Research BenchVals AI55.3%†45.2%
SkillsBenchVals AI60.4%†–
SREBenchVals AI12.2%†–
Tax Agent BenchVals AI45.5%†44.4%
Terminal-Bench 4.0 (Vals)Vals AI53.5%†31.8%
Terminal-Bench ScienceVals AI27.1%†–
Time Horizon Index: KSPVals AI18.8%†–
Arena SearchArena (LMArena)1214†–
BALROGBALROG63.4%–
PostTrainBenchEpoch AI Benchmarking Hub35.0%†–
GBAEvalEpoch AI Benchmarking Hub79.6%†–
Vending-Bench 2Andon Labs11181.9†–
AutomationBenchArtificial Analysis56.6%66.6%
GDP.pdf (AA)Artificial Analysis21.6%17.2%
EnterpriseOps-GymArtificial Analysis47.5%–
AA-Briefcase v1.1Artificial Analysis16571570
Terminal-Bench-Science 0.1 (AA)Artificial Analysis28.6%12.9%
CWE-Bench (AA)Artificial Analysis–69.2%
DeepSec-Bench (AA)Artificial Analysis25.9%24.9%
CyberGym end-to-end (AA)Artificial Analysis–76.3%
FACTS SearchGoogle85.3%†–
Maths
FrontierMath Tiers 1–3Epoch AI Benchmarking Hub85.6%71.2%
FrontierMath Tier 4Epoch AI Benchmarking Hub73.2%46.3%
OTIS Mock AIMEEpoch AI Benchmarking Hub98.9%99.4%
ProofBenchVals AI99.0%–
LiveBench MathematicsLiveBench95.7%–
Arena MathsArena (LMArena)1517–
Knowledge
SimpleQA VerifiedEpoch AI Benchmarking Hub59.9%42.5%
LiveBench 2.0 Data AnalysisLiveBench74.6%†79.5%†
LiveBench ResearchLiveBench88.9%†79.5%†
LiveBench 1.0 Data AnalysisLiveBench74.5%–
AA-OmniscienceArtificial Analysis37.14.7
MMLU-ProVals AI91.6%†–
LegalBenchVals AI87.0%†–
CorpFinVals AI73.2%†–
TaxEvalVals AI75.1%†–
BioMysteryBenchVals AI79.3%†–
Excel Modeling BenchmarkVals AI73.6%†61.8%
Excel Modeling Benchmark v1.1Vals AI–69.2%
MedCodeVals AI63.6%†–
MedScribeVals AI91.0%†–
Public Benefits Bench v1.1Vals AI76.9%†–
DrugDiscoveryBenchScale AI SEAL53.7%–
EBR-benchEpoch AI Benchmarking Hub45.7%–
GDP.pdfEpoch AI Benchmarking Hub24.0%–
AA-Omniscience: accuracyArtificial Analysis60.9%42.9%
AA-Omniscience: non-hallucinationArtificial Analysis39.2%33.3%
Instruction following
LiveBench LanguageLiveBench88.7%–
LiveBench Instruction FollowingLiveBench63.8%–
Arena Instruction FollowingArena (LMArena)1495–
Human preference
Arena TextArena (LMArena)1491–
EQ-Bench 4EQ-Bench1385†–
Arena Creative WritingArena (LMArena)1474–
Arena Multi-turnArena (LMArena)1487–
Arena Longer QueriesArena (LMArena)1503–
Multimodal
Arena VisionArena (LMArena)1320†–
LiveBench DesignLiveBench83.0%†83.4%†
MMMU-ProArtificial Analysis84.7%80.6%
MMMU-Pro (Vals)Vals AI89.9%†–
MortgageTaxVals AI72.1%†–
SAGEVals AI49.4%†–
Blueprint-Bench 2Epoch AI Benchmarking Hub30.4%†–
Long context
AA-LCRArtificial Analysis79.3%82.7%
Arena DocumentArena (LMArena)1490†–
MLCRArtificial Analysis11.1%26.7%
Composite
Epoch Capabilities IndexEpoch AI Benchmarking Hub163.9†–
LiveBench 2.0LiveBench82.1%†79.2%†
LiveBench 1.0LiveBench80.1%–
AA Intelligence Index v4.3.2Artificial Analysis50.845.1
Vals IndexVals AI–61.3
Vals Finance IndexVals AI–60.9%
Vals RSI IndexVals AI33.0%–
Vals Science IndexVals AI47.9%†–
Vals Multimodal IndexVals AI73.9%†–
Vals Router IndexVals AI–61.3%†
AA Cyber IndexArtificial Analysis–56.8
Safety & honesty
FORTRESSScale AI SEAL16.8%†–
Metadata
AA Openness IndexArtificial Analysis–44.4

Data as of 2026-10-24. 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).
  • DeepSeek V4.1 Flash 1017 (max): 10 new results (MLCR, AA Cyber Index, CWE-Bench (AA)…).
  • DeepSeek V4.1 Flash 1017 (max): BenchLeader Index 63.1 → 63.9.
  • Claude Opus 5 (max): 1 score revision.
  • DeepSeek V4.1 Flash 1017 (max): 11 new results (GPQA Diamond, FrontierMath Tiers 1–3, FrontierMath Tier 4…).
  • Claude Opus 5 (max): 1 new result (ForecastBench); 1 score revision.
  • DeepSeek V4.1 Flash 1017 (max): 1 new result (FrontierCode 1.1 (AA)); 2 score revisions.
  • Claude Opus 5 (max): BenchLeader Index 68.3 → 68.9.
  • Claude Opus 5 (max): 4 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 DeepSeek V4.1 Flash 1017: questions

Is Claude Opus 5 better than DeepSeek V4.1 Flash 1017?
Claude Opus 5 (max) leads on quality: 68.8 vs 64.0. The BenchLeader Index combines every independent quality benchmark; Claude Opus 5 (max) is ahead overall as of 2026-10-24, but check the category scores for your use.
Which is cheaper, Claude Opus 5 or DeepSeek V4.1 Flash 1017, and will that change?
DeepSeek V4.1 Flash 1017 is cheaper today: $0.525 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 DeepSeek V4.1 Flash 1017 for coding?
They are level in coding (70 vs 70 on the category index). On Arena WebDev, the top shared coding benchmark, it is 1690 for Claude Opus 5 against 1664 for DeepSeek V4.1 Flash 1017.
Is Claude Opus 5 better than DeepSeek V4.1 Flash 1017 for agents and tool use?
Claude Opus 5 scores higher in agentic tasks (64 vs 63 on the category index, where 50 is average). On DeepSec-Bench (AA), the top shared agents & tools benchmark, it is 25.9% for Claude Opus 5 against 24.9% for DeepSeek V4.1 Flash 1017.
Which is better for long documents?
DeepSeek V4.1 Flash 1017 scores higher on long-context benchmarks (66 vs 65). Both take about 1M tokens: Claude Opus 5 1,000,000, DeepSeek V4.1 Flash 1017 1,048,576.
Which has lower latency?
DeepSeek V4.1 Flash 1017 (max) answers first: 11.2 s against 20.2 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 DeepSeek V4.1 Flash 1017?
DeepSeek V4.1 Flash 1017 streams faster: 198 against 57 output tokens per second.
Do independent benchmarks agree on Claude Opus 5 vs DeepSeek V4.1 Flash 1017?
Across the 25 benchmarks both have, Claude Opus 5 leads 20, DeepSeek V4.1 Flash 1017 leads 5. Every overall index that rates both puts Claude Opus 5 ahead.
When was DeepSeek V4.1 Flash 1017 released?
DeepSeek V4.1 Flash 1017 was released on 17 Oct 2026.