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Claude Opus 4.6 vs DeepSeek V4 Flash 0423

Updated October 21, 2026. 45 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.

Replace Claude Opus 4.6 Replace DeepSeek V4 Flash 0423
Claude Opus 4.6Anthropic
Coding
66.9
Overall
31.9
Output $/M
$25.00
43
DeepSeek V4 Flash 0423DeepSeek
Coding
54.6
Overall
24.4
Output $/M
$0.182
2
vs boards won of 45 shared

Decision reading

Pick Claude Opus 4.6 for coding: it scores 66.9 on the Vibe Coding Index against 54.6 for DeepSeek V4 Flash 0423.

Pick DeepSeek V4 Flash 0423 when output tokens cost 137.4x less, or when the context window is larger, 1.05M against 1M tokens.

Model AClaude Opus 4.6Anthropic66.9/1002 independent benchmarks$1.56 per solved taskModel BDeepSeek V4 Flash 0423DeepSeek54.6/1001 independent benchmarkNo cost per solved task
Shared results
45
Claude Opus 4.6 only
63
DeepSeek V4 Flash 0423 only
3
Like-for-like categories
7 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 4.6 66.9 from 2 benchmarks, DeepSeek V4 Flash 0423 54.6 from 1 benchmark.
Widest category
Reasoning, 16.3 points apart on average over 4 shared benchmarks.
Widest single gap
WeirdML: Claude Opus 4.6 78.0% against DeepSeek V4 Flash 0423 45.6%, 32.3 points apart on a 0 to 100 scale.
Output price
Claude Opus 4.6 $25.00 against DeepSeek V4 Flash 0423 $0.182 per million output tokens, 137.4x apart.
Context window
Claude Opus 4.6 takes 1M tokens, DeepSeek V4 Flash 0423 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 4.6BarsDeepSeek V4 Flash 0423Ties
Coding42
Intelligence20
Reasoning40
Math20
Knowledge40
Web design80
General190
All shared boards432
CodingLike-for-likeFour of these boards feed the Vibe Coding Index42
Coding benchmarks for Claude Opus 4.6 and DeepSeek V4 Flash 0423
BenchmarkClaude Opus 4.6DeepSeek V4 Flash 0423Leader
SWE-bench Verified75.6%Not measuredOnly Claude Opus 4.6 measured
SWE-bench Multilingual72.0%Not measuredOnly Claude Opus 4.6 measured
LMArena WebDev15471582DeepSeek V4 Flash 0423
AA Coding IndexNot measured52.0Only DeepSeek V4 Flash 0423 measured
LiveCodeBench (Vals AI)84.7%Not measuredOnly Claude Opus 4.6 measured
SWE-bench Verified (Vals AI)78.2%Not measuredOnly Claude Opus 4.6 measured
Vibe Code Bench (Vals AI)57.6%Not measuredOnly Claude Opus 4.6 measured
Terminal-Bench Hard (Artificial Analysis run)48.5%Not measuredOnly Claude Opus 4.6 measured
Terminal-Bench79.8%Not measuredOnly Claude Opus 4.6 measured
FrontierCode26.6%Not measuredOnly Claude Opus 4.6 measured
GSO-Bench41.2%Not measuredOnly Claude Opus 4.6 measured
WeirdML78.0%45.6%Claude Opus 4.6
Cybench93.0%Not measuredOnly Claude Opus 4.6 measured
ALE-BenchNot measured678.2Only DeepSeek V4 Flash 0423 measured
LMArena Text: coding15341457Claude Opus 4.6
LMArena Text: software and IT15271453Claude Opus 4.6
LMArena WebDev: React15391585DeepSeek V4 Flash 0423
LMArena WebDev: HTML15591558Claude Opus 4.6
LMArena WebDev: from an image1543Not measuredOnly Claude Opus 4.6 measured
Neither model has a result on the other 19 boards here
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
Intelligence benchmarks for Claude Opus 4.6 and DeepSeek V4 Flash 0423
BenchmarkClaude Opus 4.6DeepSeek V4 Flash 0423Leader
AA Intelligence Index31.924.4Claude Opus 4.6
Epoch Capabilities Index155.7146.1Claude Opus 4.6
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index12 boards, none shared
Agentic work benchmarks for Claude Opus 4.6 and DeepSeek V4 Flash 0423
BenchmarkClaude Opus 4.6DeepSeek V4 Flash 0423Leader
AA Agentic IndexNot measured26.3Only DeepSeek V4 Flash 0423 measured
Design Arena: agents building web apps1206Not measuredOnly Claude Opus 4.6 measured
Design Arena: agents building full-stack apps1220Not measuredOnly Claude Opus 4.6 measured
Design Arena: agents building mobile apps1207Not measuredOnly Claude Opus 4.6 measured
Design Arena: agents building Android apps1204Not measuredOnly Claude Opus 4.6 measured
Design Arena: agents building games1214Not measuredOnly Claude Opus 4.6 measured
τ²-Bench Telecom92.1%Not measuredOnly Claude Opus 4.6 measured
APEX-Agents46.3%Not measuredOnly Claude Opus 4.6 measured
METR time horizons78.9%Not measuredOnly Claude Opus 4.6 measured
Remote Labor Index4.2%Not measuredOnly Claude Opus 4.6 measured
DeepResearch Bench55.3%Not measuredOnly Claude Opus 4.6 measured
Vending-Bench 2$8,018Not measuredOnly Claude Opus 4.6 measured
Neither model has a result on the other 27 boards here
ReasoningLike-for-likePublic boards, shown as published, kept out of the index40
Reasoning benchmarks for Claude Opus 4.6 and DeepSeek V4 Flash 0423
BenchmarkClaude Opus 4.6DeepSeek V4 Flash 0423Leader
GPQA Diamond89.7%Not measuredOnly Claude Opus 4.6 measured
MMMU Pro (Vals AI)83.9%Not measuredOnly Claude Opus 4.6 measured
GPQA Diamond (Artificial Analysis run)89.6%Not measuredOnly Claude Opus 4.6 measured
Humanity's Last Exam (Artificial Analysis run)39.9%Not measuredOnly Claude Opus 4.6 measured
GPQA Diamond (Epoch AI run)90.5%Not measuredOnly Claude Opus 4.6 measured
ARC-AGI94.0%Not measuredOnly Claude Opus 4.6 measured
ARC-AGI-269.2%Not measuredOnly Claude Opus 4.6 measured
SimpleBench67.6%46.3%Claude Opus 4.6
Chess puzzles21.0%Not measuredOnly Claude Opus 4.6 measured
Mystery game puzzles25.0%Not measuredOnly Claude Opus 4.6 measured
EBR-bench12.7%Not measuredOnly Claude Opus 4.6 measured
LMArena Text: hard prompts15251444Claude Opus 4.6
LMArena Text: expert15441441Claude Opus 4.6
LMArena Text: hard prompts in English15301449Claude Opus 4.6
LMArena Vision: diagrams1340Not measuredOnly Claude Opus 4.6 measured
LMArena Vision: homework1337Not measuredOnly Claude Opus 4.6 measured
Neither model has a result on the other 5 boards here
MathLike-for-likePublic boards, shown as published, kept out of the index20
Math benchmarks for Claude Opus 4.6 and DeepSeek V4 Flash 0423
BenchmarkClaude Opus 4.6DeepSeek V4 Flash 0423Leader
AIME95.6%Not measuredOnly Claude Opus 4.6 measured
OTIS Mock AIME94.4%Not measuredOnly Claude Opus 4.6 measured
FrontierMath, tiers 1 to 366.0%Not measuredOnly Claude Opus 4.6 measured
FrontierMath, tier 426.8%Not measuredOnly Claude Opus 4.6 measured
ProofBench50.0%Not measuredOnly Claude Opus 4.6 measured
LMArena Text: math15181426Claude Opus 4.6
LMArena Text: mathematical work15251432Claude Opus 4.6
Neither model has a result on the other 6 boards here
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index40
Knowledge benchmarks for Claude Opus 4.6 and DeepSeek V4 Flash 0423
BenchmarkClaude Opus 4.6DeepSeek V4 Flash 0423Leader
MMLU Pro89.1%Not measuredOnly Claude Opus 4.6 measured
LegalBench (Vals AI)85.3%Not measuredOnly Claude Opus 4.6 measured
CaseLaw (Vals AI)62.1%Not measuredOnly Claude Opus 4.6 measured
CorpFin (Vals AI)67.0%Not measuredOnly Claude Opus 4.6 measured
TaxEval (Vals AI)76.0%Not measuredOnly Claude Opus 4.6 measured
MortgageTax (Vals AI)68.5%Not measuredOnly Claude Opus 4.6 measured
MedQA (Vals AI)95.4%Not measuredOnly Claude Opus 4.6 measured
MedCode (Vals AI)49.1%Not measuredOnly Claude Opus 4.6 measured
SimpleQA Verified47.0%Not measuredOnly Claude Opus 4.6 measured
LMArena Text: science15191446Claude Opus 4.6
LMArena Text: medicine and healthcare15041448Claude Opus 4.6
LMArena Text: legal and government15121439Claude Opus 4.6
LMArena Text: business and finance14971425Claude Opus 4.6
Neither model has a result on the other 4 boards here
Web designLike-for-likePublic boards, shown as published, kept out of the index80
Web design benchmarks for Claude Opus 4.6 and DeepSeek V4 Flash 0423
BenchmarkClaude Opus 4.6DeepSeek V4 Flash 0423Leader
Design Arena: websites12911208Claude Opus 4.6
Design Arena: UI components12841164Claude Opus 4.6
Design Arena: game dev12781197Claude Opus 4.6
Design Arena: data viz12791127Claude Opus 4.6
Design Arena: 3D12741189Claude Opus 4.6
Design Arena: all code categories12891205Claude Opus 4.6
Design Arena: SVG12271155Claude Opus 4.6
Design Arena: ASCII art12541109Claude Opus 4.6
Neither model has a result on the other 1 board here
GeneralLike-for-likePublic boards, shown as published, kept out of the index190
General benchmarks for Claude Opus 4.6 and DeepSeek V4 Flash 0423
BenchmarkClaude Opus 4.6DeepSeek V4 Flash 0423Leader
SAGE (Vals AI)51.6%Not measuredOnly Claude Opus 4.6 measured
MedScribe (Vals AI)86.7%Not measuredOnly Claude Opus 4.6 measured
IFBench53.1%Not measuredOnly Claude Opus 4.6 measured
Long context reasoning (AA-LCR)78.0%Not measuredOnly Claude Opus 4.6 measured
DTBench91.2%86.4%Claude Opus 4.6
LMCA55.8%35.9%Claude Opus 4.6
CL-bench20.7%Not measuredOnly Claude Opus 4.6 measured
Furniture assembly28.3%Not measuredOnly Claude Opus 4.6 measured
CL-bench Life17.0%Not measuredOnly Claude Opus 4.6 measured
LMArena Text15011432Claude Opus 4.6
LMArena Text: instruction following15211421Claude Opus 4.6
LMArena Text: creative writing15051403Claude Opus 4.6
LMArena Vision1316Not measuredOnly Claude Opus 4.6 measured
LMArena Text: English15111441Claude Opus 4.6
LMArena Text: non-English14881419Claude Opus 4.6
LMArena Text: Chinese15511463Claude Opus 4.6
LMArena Text: German15001419Claude Opus 4.6
LMArena Text: Japanese14881389Claude Opus 4.6
LMArena Text: Korean14641383Claude Opus 4.6
LMArena Text: French15121439Claude Opus 4.6
LMArena Text: Spanish15101436Claude Opus 4.6
LMArena Text: Russian14971427Claude Opus 4.6
LMArena Text: Polish14991436Claude Opus 4.6
LMArena Text: multi-turn15111449Claude Opus 4.6
LMArena Text: longer queries15181434Claude Opus 4.6
LMArena Text: writing and language15021410Claude Opus 4.6
LMArena Text: entertainment and media14921400Claude Opus 4.6
LMArena Vision: English1324Not measuredOnly Claude Opus 4.6 measured
LMArena Vision: Chinese1370Not measuredOnly Claude Opus 4.6 measured
LMArena Vision: reading text1326Not measuredOnly Claude Opus 4.6 measured
LMArena Vision: humor1314Not measuredOnly Claude Opus 4.6 measured
LMArena Vision: recognizing things1274Not measuredOnly Claude Opus 4.6 measured
LMArena Vision: creative writing1331Not measuredOnly Claude Opus 4.6 measured
LMArena Document1507Not measuredOnly Claude Opus 4.6 measured
Neither model has a result on the other 12 boards here
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
Image generation benchmarks for Claude Opus 4.6 and DeepSeek V4 Flash 0423
BenchmarkClaude Opus 4.6DeepSeek V4 Flash 0423Leader
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 4.6$0.018Fits in one request
DeepSeek V4 Flash 0423$0.0002Fits in one request

DeepSeek V4 Flash 0423 costs less

Repository review

50K input + 3K output tokens

Claude Opus 4.6$0.325Fits in one request
DeepSeek V4 Flash 0423$0.0051Fits in one request

DeepSeek V4 Flash 0423 costs less

Agent loop

200K input + 10K output tokens

Claude Opus 4.6$1.25Fits in one request
DeepSeek V4 Flash 0423$0.020Fits in one request

DeepSeek V4 Flash 0423 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 4.6 and DeepSeek V4 Flash 0423
SpecificationAnthropic Claude Opus 4.6DeepSeek V4 Flash 0423
MakerAnthropicDeepSeek
WeightsNo public weights listedOpen weights
ReleasedFebruary 4, 2026April 24, 2026
Context window1M1.05M
Input $/Mtok$5.00$0.091
Output $/Mtok$25.00$0.182
Coding index66.954.6
Independent measurements behind it21
Cost per solved task$1.56Not computable
SourceOpenRouter listingOpenRouter listing

Questions

Is Claude Opus 4.6 better than DeepSeek V4 Flash 0423 for coding?

Pick Claude Opus 4.6 for coding: it scores 66.9 on the Vibe Coding Index against 54.6 for DeepSeek V4 Flash 0423. Pick DeepSeek V4 Flash 0423 when output tokens cost 137.4x less, or when the context window is larger, 1.05M against 1M tokens.

Which is cheaper, Claude Opus 4.6 or DeepSeek V4 Flash 0423?

Claude Opus 4.6 costs $5.00 per million input tokens and $25.00 per million output tokens; DeepSeek V4 Flash 0423 costs $0.091 and $0.182. Cost per solved task is known for Claude Opus 4.6 only.

Which has the bigger context window, Claude Opus 4.6 or DeepSeek V4 Flash 0423?

DeepSeek V4 Flash 0423, with 1.05M tokens against 1M.

How many benchmarks is the Claude Opus 4.6 vs DeepSeek V4 Flash 0423 comparison based on?

45 benchmarks have a result for both models as of October 21, 2026. Claude Opus 4.6's coding index rests on 2 independent benchmarks and DeepSeek V4 Flash 0423's on 1. Where only one model has a result, the page says so instead of naming a winner.

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