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Claude Opus 4.8 vs DeepSeek V4.1 Flash 1017

Updated October 21, 2026. 28 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.

Claude Opus 4.8Anthropic
Coding
66.0
Overall
41.8
Output $/M
$25.00
8
DeepSeek V4.1 Flash 1017DeepSeek
Coding
83.3
Overall
39.5
Output $/M
$0.60
20
vs boards won of 28 shared

Decision reading

Pick DeepSeek V4.1 Flash 1017 for coding: it scores 83.3 on the Vibe Coding Index against 66.0 for Claude Opus 4.8.

Pick Claude Opus 4.8 when what matters is Code migration (Vals AI) or AA Intelligence Index, where it leads.

Shared results
28
Claude Opus 4.8 only
98
DeepSeek V4.1 Flash 1017 only
4
Like-for-like categories
6 of 9

Shared results can support a head-to-head reading. Results only one model has describe coverage, not superiority.

Which one for your work

Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.

At a glance

Coding index
Claude Opus 4.8 66.0 from 2 benchmarks, DeepSeek V4.1 Flash 1017 83.3 from 2 benchmarks.
Widest category
General, 9.3 points apart on average over 2 shared benchmarks.
Widest single gap
LiveBench browser: Claude Opus 4.8 96.0% against DeepSeek V4.1 Flash 1017 76.0%, 20.0 points apart on a 0 to 100 scale.
Output price
Claude Opus 4.8 $25.00 against DeepSeek V4.1 Flash 1017 $0.60 per million output tokens, 41.7x apart.
Context window
Claude Opus 4.8 takes 1M tokens, DeepSeek V4.1 Flash 1017 1.05M.

Benchmark by benchmark

First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.

Boards won, where both have a result
CategoryClaude Opus 4.8BarsDeepSeek V4.1 Flash 1017Ties
Coding17
Intelligence10
Agentic work34
Reasoning20
Web design17
General02
All shared boards820
CodingLike-for-likeFour of these boards feed the Vibe Coding Index17
Coding benchmarks for Claude Opus 4.8 and DeepSeek V4.1 Flash 1017
BenchmarkClaude Opus 4.8DeepSeek V4.1 Flash 1017Leader
LiveBench coding77.3%96.0%DeepSeek V4.1 Flash 1017
LMArena WebDev15561664DeepSeek V4.1 Flash 1017
AA Coding Index74.3Not measuredOnly Claude Opus 4.8 measured
LiveCodeBench (Vals AI)87.8%Not measuredOnly Claude Opus 4.8 measured
SWE-bench Verified (Vals AI)88.6%Not measuredOnly Claude Opus 4.8 measured
Terminal-Bench 4 (Vals AI)23.2%31.8%DeepSeek V4.1 Flash 1017
Vibe Code Bench (Vals AI)82.7%87.7%DeepSeek V4.1 Flash 1017
Code migration (Vals AI)47.3%44.2%Claude Opus 4.8
ProgramBench (Vals AI)1.0%Not measuredOnly Claude Opus 4.8 measured
Terminal-Bench 2.1 (Vals AI)71.9%Not measuredOnly Claude Opus 4.8 measured
SkillsBench (Vals AI)59.2%Not measuredOnly Claude Opus 4.8 measured
SciCode54.4%55.9%DeepSeek V4.1 Flash 1017
Terminal-Bench Hard (Artificial Analysis run)58.3%Not measuredOnly Claude Opus 4.8 measured
FrontierCode46.5%Not measuredOnly Claude Opus 4.8 measured
GSO-Bench47.1%Not measuredOnly Claude Opus 4.8 measured
WeirdML82.9%Not measuredOnly Claude Opus 4.8 measured
ALE-BenchNot measured1622.0Only DeepSeek V4.1 Flash 1017 measured
LMArena Text: coding1490Not measuredOnly Claude Opus 4.8 measured
LMArena Text: software and IT1488Not measuredOnly Claude Opus 4.8 measured
LMArena WebDev: React15571667DeepSeek V4.1 Flash 1017
LMArena WebDev: HTML15431687DeepSeek V4.1 Flash 1017
Neither model has a result on the other 17 boards here
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
Intelligence benchmarks for Claude Opus 4.8 and DeepSeek V4.1 Flash 1017
BenchmarkClaude Opus 4.8DeepSeek V4.1 Flash 1017Leader
AA Intelligence Index41.839.5Claude Opus 4.8
Epoch Capabilities Index159.0Not measuredOnly Claude Opus 4.8 measured
Agentic workLike-for-likePublic boards, shown as published, kept out of the index34
Agentic work benchmarks for Claude Opus 4.8 and DeepSeek V4.1 Flash 1017
BenchmarkClaude Opus 4.8DeepSeek V4.1 Flash 1017Leader
AA Agentic Index41.9Not measuredOnly Claude Opus 4.8 measured
Design Arena: agents building web apps1233Not measuredOnly Claude Opus 4.8 measured
Design Arena: agents building full-stack apps1249Not measuredOnly Claude Opus 4.8 measured
Design Arena: agents building mobile apps1222Not measuredOnly Claude Opus 4.8 measured
Design Arena: agents building Android apps1237Not measuredOnly Claude Opus 4.8 measured
Design Arena: agents building Godot games1231Not measuredOnly Claude Opus 4.8 measured
Design Arena: agents building games1238Not measuredOnly Claude Opus 4.8 measured
Design Arena: HTML slides1221Not measuredOnly Claude Opus 4.8 measured
Design Arena: PowerPoint slides1227Not measuredOnly Claude Opus 4.8 measured
Design Arena: spreadsheetsNot measured1238Only DeepSeek V4.1 Flash 1017 measured
LiveBench research81.8%79.5%Claude Opus 4.8
LiveBench browser96.0%76.0%Claude Opus 4.8
LiveBench long agentic48.3%50.9%DeepSeek V4.1 Flash 1017
Finance Agent (Vals AI)53.9%57.0%DeepSeek V4.1 Flash 1017
Tax Agent Bench (Vals AI)30.0%44.4%DeepSeek V4.1 Flash 1017
Legal Research Bench (Vals AI)43.8%45.2%DeepSeek V4.1 Flash 1017
Harvey's Legal Agent Benchmark (Vals AI)Not measured14.2%Only DeepSeek V4.1 Flash 1017 measured
Excel Modeling Benchmark (Vals AI)69.4%61.8%Claude Opus 4.8
Terminal-Bench-Science (Vals AI)4.3%Not measuredOnly Claude Opus 4.8 measured
Time Horizon Index (Vals AI)11.8%Not measuredOnly Claude Opus 4.8 measured
τ²-Bench Telecom94.4%Not measuredOnly Claude Opus 4.8 measured
APEX-Agents48.9%Not measuredOnly Claude Opus 4.8 measured
Remote Labor Index8.3%Not measuredOnly Claude Opus 4.8 measured
OSWorld 2.020.6%Not measuredOnly Claude Opus 4.8 measured
DeepResearch Bench50.2%Not measuredOnly Claude Opus 4.8 measured
PostTrainBench33.8%Not measuredOnly Claude Opus 4.8 measured
Vending-Bench 2$5,787Not measuredOnly Claude Opus 4.8 measured
LMArena Search1204Not measuredOnly Claude Opus 4.8 measured
Neither model has a result on the other 11 boards here
ReasoningLike-for-likePublic boards, shown as published, kept out of the index20
Reasoning benchmarks for Claude Opus 4.8 and DeepSeek V4.1 Flash 1017
BenchmarkClaude Opus 4.8DeepSeek V4.1 Flash 1017Leader
GPQA Diamond92.4%Not measuredOnly Claude Opus 4.8 measured
LiveBench reasoning89.2%89.1%Claude Opus 4.8
MMMU Pro (Vals AI)86.6%Not measuredOnly Claude Opus 4.8 measured
GPQA Diamond (Artificial Analysis run)92.0%Not measuredOnly Claude Opus 4.8 measured
Humanity's Last Exam (Artificial Analysis run)48.7%43.3%Claude Opus 4.8
GPQA Diamond (Epoch AI run)91.0%Not measuredOnly Claude Opus 4.8 measured
ARC-AGI92.5%Not measuredOnly Claude Opus 4.8 measured
ARC-AGI-272.1%Not measuredOnly Claude Opus 4.8 measured
SimpleBench64.8%Not measuredOnly Claude Opus 4.8 measured
Chess puzzles52.0%Not measuredOnly Claude Opus 4.8 measured
Mystery game puzzles36.0%Not measuredOnly Claude Opus 4.8 measured
EBR-bench28.6%Not measuredOnly Claude Opus 4.8 measured
LMArena Text: hard prompts1482Not measuredOnly Claude Opus 4.8 measured
LMArena Text: expert1503Not measuredOnly Claude Opus 4.8 measured
LMArena Text: hard prompts in English1487Not measuredOnly Claude Opus 4.8 measured
LMArena Vision: diagrams1315Not measuredOnly Claude Opus 4.8 measured
LMArena Vision: homework1337Not measuredOnly Claude Opus 4.8 measured
Neither model has a result on the other 4 boards here
MathDirectional onlyPublic boards, shown as published, kept out of the index6 boards, none shared
Math benchmarks for Claude Opus 4.8 and DeepSeek V4.1 Flash 1017
BenchmarkClaude Opus 4.8DeepSeek V4.1 Flash 1017Leader
OTIS Mock AIME98.3%Not measuredOnly Claude Opus 4.8 measured
FrontierMath, tiers 1 to 380.0%Not measuredOnly Claude Opus 4.8 measured
FrontierMath, tier 456.1%Not measuredOnly Claude Opus 4.8 measured
ProofBench69.0%Not measuredOnly Claude Opus 4.8 measured
LMArena Text: math1486Not measuredOnly Claude Opus 4.8 measured
LMArena Text: mathematical work1497Not measuredOnly Claude Opus 4.8 measured
Neither model has a result on the other 7 boards here
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index11 boards, none shared
Knowledge benchmarks for Claude Opus 4.8 and DeepSeek V4.1 Flash 1017
BenchmarkClaude Opus 4.8DeepSeek V4.1 Flash 1017Leader
MMLU Pro89.6%Not measuredOnly Claude Opus 4.8 measured
LegalBench (Vals AI)83.6%Not measuredOnly Claude Opus 4.8 measured
CorpFin (Vals AI)66.7%Not measuredOnly Claude Opus 4.8 measured
TaxEval (Vals AI)75.6%Not measuredOnly Claude Opus 4.8 measured
MortgageTax (Vals AI)69.9%Not measuredOnly Claude Opus 4.8 measured
MedCode (Vals AI)53.2%Not measuredOnly Claude Opus 4.8 measured
SimpleQA Verified53.0%Not measuredOnly Claude Opus 4.8 measured
LMArena Text: science1477Not measuredOnly Claude Opus 4.8 measured
LMArena Text: medicine and healthcare1464Not measuredOnly Claude Opus 4.8 measured
LMArena Text: legal and government1477Not measuredOnly Claude Opus 4.8 measured
LMArena Text: business and finance1458Not measuredOnly Claude Opus 4.8 measured
Neither model has a result on the other 6 boards here
Web designLike-for-likePublic boards, shown as published, kept out of the index17
Web design benchmarks for Claude Opus 4.8 and DeepSeek V4.1 Flash 1017
BenchmarkClaude Opus 4.8DeepSeek V4.1 Flash 1017Leader
Design Arena: websites12581312DeepSeek V4.1 Flash 1017
Design Arena: UI components12561305DeepSeek V4.1 Flash 1017
Design Arena: game dev12641365DeepSeek V4.1 Flash 1017
Design Arena: data viz12401330DeepSeek V4.1 Flash 1017
Design Arena: 3D12231368DeepSeek V4.1 Flash 1017
Design Arena: all code categories12551335DeepSeek V4.1 Flash 1017
Design Arena: SVG1194Not measuredOnly Claude Opus 4.8 measured
Design Arena: ASCII art12761244Claude Opus 4.8
LiveBench design78.8%83.4%DeepSeek V4.1 Flash 1017
GeneralLike-for-likePublic boards, shown as published, kept out of the index02
General benchmarks for Claude Opus 4.8 and DeepSeek V4.1 Flash 1017
BenchmarkClaude Opus 4.8DeepSeek V4.1 Flash 1017Leader
Vals IndexNot measured61.3%Only DeepSeek V4.1 Flash 1017 measured
LiveBench data analysis66.0%79.5%DeepSeek V4.1 Flash 1017
Public Benefits Bench (Vals AI)68.1%Not measuredOnly Claude Opus 4.8 measured
SAGE (Vals AI)54.8%Not measuredOnly Claude Opus 4.8 measured
MedScribe (Vals AI)85.8%Not measuredOnly Claude Opus 4.8 measured
Vals Multimodal Index70.9%Not measuredOnly Claude Opus 4.8 measured
IFBench62.2%Not measuredOnly Claude Opus 4.8 measured
Long context reasoning (AA-LCR)77.7%82.7%DeepSeek V4.1 Flash 1017
DTBench94.9%Not measuredOnly Claude Opus 4.8 measured
LMCA57.5%Not measuredOnly Claude Opus 4.8 measured
Surface Evolver Bench87.5%Not measuredOnly Claude Opus 4.8 measured
Furniture assembly42.5%Not measuredOnly Claude Opus 4.8 measured
LMArena Text1461Not measuredOnly Claude Opus 4.8 measured
LMArena Text: instruction following1476Not measuredOnly Claude Opus 4.8 measured
LMArena Text: creative writing1454Not measuredOnly Claude Opus 4.8 measured
LMArena Vision1294Not measuredOnly Claude Opus 4.8 measured
LMArena Text: English1468Not measuredOnly Claude Opus 4.8 measured
LMArena Text: non-English1450Not measuredOnly Claude Opus 4.8 measured
LMArena Text: Chinese1506Not measuredOnly Claude Opus 4.8 measured
LMArena Text: German1472Not measuredOnly Claude Opus 4.8 measured
LMArena Text: Japanese1442Not measuredOnly Claude Opus 4.8 measured
LMArena Text: Korean1431Not measuredOnly Claude Opus 4.8 measured
LMArena Text: French1481Not measuredOnly Claude Opus 4.8 measured
LMArena Text: Spanish1465Not measuredOnly Claude Opus 4.8 measured
LMArena Text: Russian1474Not measuredOnly Claude Opus 4.8 measured
LMArena Text: Polish1459Not measuredOnly Claude Opus 4.8 measured
LMArena Text: multi-turn1476Not measuredOnly Claude Opus 4.8 measured
LMArena Text: longer queries1483Not measuredOnly Claude Opus 4.8 measured
LMArena Text: writing and language1461Not measuredOnly Claude Opus 4.8 measured
LMArena Text: entertainment and media1440Not measuredOnly Claude Opus 4.8 measured
LMArena Vision: English1293Not measuredOnly Claude Opus 4.8 measured
LMArena Vision: Chinese1346Not measuredOnly Claude Opus 4.8 measured
LMArena Vision: reading text1303Not measuredOnly Claude Opus 4.8 measured
LMArena Vision: humor1282Not measuredOnly Claude Opus 4.8 measured
LMArena Vision: creative writing1301Not measuredOnly Claude Opus 4.8 measured
LMArena Document1475Not measuredOnly Claude Opus 4.8 measured
Neither model has a result on the other 10 boards here
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
Image generation benchmarks for Claude Opus 4.8 and DeepSeek V4.1 Flash 1017
BenchmarkClaude Opus 4.8DeepSeek V4.1 Flash 1017Leader
Neither model has a result on 5 boards here

What each workload costs

Three fixed token mixes at each model's listed price, so per-token rates become a bill.

Chat turn

1K input + 500 output tokens

Claude Opus 4.8$0.018Fits in one request
DeepSeek V4.1 Flash 1017$0.0004Fits in one request

DeepSeek V4.1 Flash 1017 costs less

Repository review

50K input + 3K output tokens

Claude Opus 4.8$0.325Fits in one request
DeepSeek V4.1 Flash 1017$0.0093Fits in one request

DeepSeek V4.1 Flash 1017 costs less

Agent loop

200K input + 10K output tokens

Claude Opus 4.8$1.25Fits in one request
DeepSeek V4.1 Flash 1017$0.036Fits in one request

DeepSeek V4.1 Flash 1017 costs less

Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.

Specification differences

The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.

Specifications of Claude Opus 4.8 and DeepSeek V4.1 Flash 1017
SpecificationAnthropic Claude Opus 4.8DeepSeek V4.1 Flash 1017
MakerAnthropicDeepSeek
WeightsNo public weights listedOpen weights
ReleasedMay 27, 2026October 17, 2026
Context window1M1.05M
Input $/Mtok$5.00$0.15
Output $/Mtok$25.00$0.60
Coding index66.083.3
Independent measurements behind it22
Cost per solved task$2.17Not computable
SourceOpenRouter listingOpenRouter listing

Questions

Is Claude Opus 4.8 better than DeepSeek V4.1 Flash 1017 for coding?

Pick DeepSeek V4.1 Flash 1017 for coding: it scores 83.3 on the Vibe Coding Index against 66.0 for Claude Opus 4.8. Pick Claude Opus 4.8 when what matters is Code migration (Vals AI) or AA Intelligence Index, where it leads.

Which is cheaper, Claude Opus 4.8 or DeepSeek V4.1 Flash 1017?

Claude Opus 4.8 costs $5.00 per million input tokens and $25.00 per million output tokens; DeepSeek V4.1 Flash 1017 costs $0.15 and $0.60. Cost per solved task is known for Claude Opus 4.8 only.

Which has the bigger context window, Claude Opus 4.8 or DeepSeek V4.1 Flash 1017?

DeepSeek V4.1 Flash 1017, with 1.05M tokens against 1M.

How many benchmarks is the Claude Opus 4.8 vs DeepSeek V4.1 Flash 1017 comparison based on?

28 benchmarks have a result for both models as of October 21, 2026. Claude Opus 4.8's coding index rests on 2 independent benchmarks and DeepSeek V4.1 Flash 1017's on 2. Where only one model has a result, the page says so instead of naming a winner.

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