Claude Opus 4.1 vs DeepSeek V4.1 Flash 1017
DeepSeek V4.1 Flash 1017 leads Claude Opus 4.1 on the Artificial Analysis Intelligence Index, 39.5 to 22.8, and DeepSeek V4.1 Flash 1017 costs 125.0x less per output token ($0.60 vs $75.00 per million). Updated October 22, 2026; 15 benchmarks have a result for both.
Claude Opus 4.1 or DeepSeek V4.1 Flash 1017: which to pick
Only DeepSeek V4.1 Flash 1017 has a coding score, 70.3 on the Vibe Coding Index; Claude Opus 4.1 has none, so the two cannot be ranked on coding.
Compare them on price, context and the boards below.
- Shared results
- 15
- Claude Opus 4.1 only
- 58
- DeepSeek V4.1 Flash 1017 only
- 24
- Like-for-like categories
- 5 of 9
Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.
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.
Coding
Vibe Coding Index, six public coding benchmarks
No call
Only DeepSeek V4.1 Flash 1017 has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
DeepSeek V4.1 Flash 1017
DeepSeek V4.1 Flash 1017 leads, 39.5 against 22.8.
Same board, both measured
Reasoning
GPQA Diamond
No call
Only Claude Opus 4.1 has a GPQA Diamond result, 76.3%.
Directional only
Math
AIME
No call
Only Claude Opus 4.1 has a AIME result, 78.2%.
Directional only
Knowledge
MMLU Pro
No call
Only Claude Opus 4.1 has a MMLU Pro result, 87.9%.
Directional only
Web design
Design Arena: websites
DeepSeek V4.1 Flash 1017
DeepSeek V4.1 Flash 1017 leads, 1311 against 1176.
Same board, both measured
General
Vals Index
No call
Only DeepSeek V4.1 Flash 1017 has a Vals Index result, 61.3%.
Directional only
Long documents
Listed context window
DeepSeek V4.1 Flash 1017
DeepSeek V4.1 Flash 1017 takes 1.05M tokens against 200K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
DeepSeek V4.1 Flash 1017
Claude Opus 4.1 $0.052, DeepSeek V4.1 Flash 1017 $0.0004 per turn.
List prices
At a glance
- Coding index
- Claude Opus 4.1 not benchmarked, DeepSeek V4.1 Flash 1017 70.3 from 4 benchmarks.
- Widest category
- Math, 44.4 points apart on average over 3 shared benchmarks.
- Widest single gap
- FrontierMath, tiers 1 to 3: Claude Opus 4.1 12.6% against DeepSeek V4.1 Flash 1017 71.2%, 58.6 points apart on a 0 to 100 scale.
- Output price
- Claude Opus 4.1 $75.00 against DeepSeek V4.1 Flash 1017 $0.60 per million output tokens, 125.0x apart.
- Context window
- Claude Opus 4.1 takes 200K 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.
| Category | Claude Opus 4.1 | Bars | DeepSeek V4.1 Flash 1017 | Ties |
|---|---|---|---|---|
| Coding | 0 | 2 | ||
| Intelligence | 0 | 1 | ||
| Reasoning | 0 | 2 | ||
| Math | 0 | 3 | ||
| Web design | 0 | 7 | ||
| All shared boards | 0 | 15 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index02
| Benchmark | Claude Opus 4.1 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| LiveBench coding | Not measured | 96.0% | Only DeepSeek V4.1 Flash 1017 measured |
| LMArena WebDev | 1390 | 1664 | DeepSeek V4.1 Flash 1017 |
| LiveCodeBench (Vals AI) | 66.5% | Not measured | Only Claude Opus 4.1 measured |
| Terminal-Bench 4 (Vals AI) | Not measured | 31.8% | Only DeepSeek V4.1 Flash 1017 measured |
| Vibe Code Bench (Vals AI) | Not measured | 87.7% | Only DeepSeek V4.1 Flash 1017 measured |
| Code migration (Vals AI) | Not measured | 44.2% | Only DeepSeek V4.1 Flash 1017 measured |
| SciCode | Not measured | 55.9% | Only DeepSeek V4.1 Flash 1017 measured |
| Terminal-Bench | 38.0% | Not measured | Only Claude Opus 4.1 measured |
| WeirdML | 45.9% | Not measured | Only Claude Opus 4.1 measured |
| Cybench | 42.0% | Not measured | Only Claude Opus 4.1 measured |
| ALE-Bench | Not measured | 1622.0 | Only DeepSeek V4.1 Flash 1017 measured |
| LMArena Text: coding | 1479 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: software and IT | 1456 | Not measured | Only Claude Opus 4.1 measured |
| LMArena WebDev: React | Not measured | 1667 | Only DeepSeek V4.1 Flash 1017 measured |
| LMArena WebDev: HTML | 1399 | 1687 | DeepSeek V4.1 Flash 1017 |
| SciCode | 4.6% | Not measured | Only Claude Opus 4.1 measured |
| Neither model has a result on the other 23 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Claude Opus 4.1 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| AA Intelligence Index | 22.8 | 39.5 | DeepSeek V4.1 Flash 1017 |
| Epoch Capabilities Index | 144.1 | Not measured | Only Claude Opus 4.1 measured |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index12 boards, none shared
| Benchmark | Claude Opus 4.1 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| Design Arena: spreadsheets | Not measured | 1245 | Only DeepSeek V4.1 Flash 1017 measured |
| LiveBench research | Not measured | 79.5% | Only DeepSeek V4.1 Flash 1017 measured |
| LiveBench browser | Not measured | 76.0% | Only DeepSeek V4.1 Flash 1017 measured |
| LiveBench long agentic | Not measured | 50.9% | Only DeepSeek V4.1 Flash 1017 measured |
| Finance Agent (Vals AI) | Not measured | 57.0% | Only DeepSeek V4.1 Flash 1017 measured |
| Tax Agent Bench (Vals AI) | Not measured | 44.4% | Only DeepSeek V4.1 Flash 1017 measured |
| Legal Research Bench (Vals AI) | Not measured | 45.2% | Only DeepSeek V4.1 Flash 1017 measured |
| Harvey's Legal Agent Benchmark (Vals AI) | Not measured | 14.2% | Only DeepSeek V4.1 Flash 1017 measured |
| Excel Modeling Benchmark (Vals AI) | Not measured | 61.8% | Only DeepSeek V4.1 Flash 1017 measured |
| METR time horizons | 66.8% | Not measured | Only Claude Opus 4.1 measured |
| GDPval | 43.6% | Not measured | Only Claude Opus 4.1 measured |
| DeepResearch Bench | 48.3% | Not measured | Only Claude Opus 4.1 measured |
| Neither model has a result on the other 29 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | Claude Opus 4.1 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| GPQA Diamond | 76.3% | Not measured | Only Claude Opus 4.1 measured |
| LiveBench reasoning | Not measured | 89.1% | Only DeepSeek V4.1 Flash 1017 measured |
| MMMU Pro (Vals AI) | 77.5% | Not measured | Only Claude Opus 4.1 measured |
| Humanity's Last Exam (Artificial Analysis run) | Not measured | 43.3% | Only DeepSeek V4.1 Flash 1017 measured |
| GPQA Diamond (Epoch AI run) | 77.3% | 93.2% | DeepSeek V4.1 Flash 1017 |
| SimpleBench | 60.0% | Not measured | Only Claude Opus 4.1 measured |
| Chess puzzles | Not measured | 46.0% | Only DeepSeek V4.1 Flash 1017 measured |
| Mystery game puzzles | 21.0% | 49.0% | DeepSeek V4.1 Flash 1017 |
| EBR-bench | 7.9% | Not measured | Only Claude Opus 4.1 measured |
| VPCT | 35.0% | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: hard prompts | 1442 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: expert | 1438 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: hard prompts in English | 1451 | Not measured | Only Claude Opus 4.1 measured |
| Neither model has a result on the other 9 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index03
| Benchmark | Claude Opus 4.1 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| AIME | 78.2% | Not measured | Only Claude Opus 4.1 measured |
| MATH 500 (Vals AI) | 95.4% | Not measured | Only Claude Opus 4.1 measured |
| MGSM (Vals AI) | 94.4% | Not measured | Only Claude Opus 4.1 measured |
| OTIS Mock AIME | 68.9% | 99.4% | DeepSeek V4.1 Flash 1017 |
| FrontierMath, tiers 1 to 3 | 12.6% | 71.2% | DeepSeek V4.1 Flash 1017 |
| FrontierMath, tier 4 | 2.4% | 46.3% | DeepSeek V4.1 Flash 1017 |
| LMArena Text: math | 1431 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: mathematical work | 1434 | Not measured | Only Claude Opus 4.1 measured |
| Neither model has a result on the other 5 boards here | |||
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index12 boards, none shared
| Benchmark | Claude Opus 4.1 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| MMLU Pro | 87.9% | Not measured | Only Claude Opus 4.1 measured |
| LegalBench (Vals AI) | 83.5% | Not measured | Only Claude Opus 4.1 measured |
| TaxEval (Vals AI) | 73.7% | Not measured | Only Claude Opus 4.1 measured |
| MortgageTax (Vals AI) | 61.1% | Not measured | Only Claude Opus 4.1 measured |
| MedQA (Vals AI) | 93.6% | Not measured | Only Claude Opus 4.1 measured |
| MedCode (Vals AI) | 47.2% | Not measured | Only Claude Opus 4.1 measured |
| SimpleQA Verified | Not measured | 42.5% | Only DeepSeek V4.1 Flash 1017 measured |
| LMArena Text: science | 1422 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: medicine and healthcare | 1416 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: legal and government | 1421 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: business and finance | 1406 | Not measured | Only Claude Opus 4.1 measured |
| FACTS Benchmark Suite | 40.4% | Not measured | Only Claude Opus 4.1 measured |
| Neither model has a result on the other 6 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index07
| Benchmark | Claude Opus 4.1 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| Design Arena: websites | 1176 | 1311 | DeepSeek V4.1 Flash 1017 |
| Design Arena: UI components | 1162 | 1303 | DeepSeek V4.1 Flash 1017 |
| Design Arena: game dev | 1171 | 1357 | DeepSeek V4.1 Flash 1017 |
| Design Arena: data viz | 1166 | 1330 | DeepSeek V4.1 Flash 1017 |
| Design Arena: 3D | 1152 | 1358 | DeepSeek V4.1 Flash 1017 |
| Design Arena: all code categories | 1170 | 1332 | DeepSeek V4.1 Flash 1017 |
| Design Arena: SVG | 1152 | Not measured | Only Claude Opus 4.1 measured |
| Design Arena: ASCII art | 1167 | 1242 | DeepSeek V4.1 Flash 1017 |
| LiveBench design | Not measured | 83.4% | Only DeepSeek V4.1 Flash 1017 measured |
GeneralDirectional onlyPublic boards, shown as published, kept out of the index25 boards, none shared
| Benchmark | Claude Opus 4.1 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| Vals Index | Not measured | 61.3% | Only DeepSeek V4.1 Flash 1017 measured |
| LiveBench data analysis | Not measured | 79.5% | Only DeepSeek V4.1 Flash 1017 measured |
| SAGE (Vals AI) | 31.4% | Not measured | Only Claude Opus 4.1 measured |
| MedScribe (Vals AI) | 73.9% | Not measured | Only Claude Opus 4.1 measured |
| Long context reasoning (AA-LCR) | Not measured | 82.7% | Only DeepSeek V4.1 Flash 1017 measured |
| DTBench | 80.0% | Not measured | Only Claude Opus 4.1 measured |
| LMCA | 37.1% | Not measured | Only Claude Opus 4.1 measured |
| Creative writing (Lech Mazur) | 84.7% | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text | 1419 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: instruction following | 1435 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: creative writing | 1412 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: English | 1433 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: non-English | 1405 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: Chinese | 1427 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: German | 1413 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: Japanese | 1377 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: Korean | 1381 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: French | 1433 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: Spanish | 1448 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: Russian | 1422 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: Polish | 1413 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: multi-turn | 1444 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: longer queries | 1455 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: writing and language | 1418 | Not measured | Only Claude Opus 4.1 measured |
| LMArena Text: entertainment and media | 1398 | Not measured | Only Claude Opus 4.1 measured |
| Neither model has a result on the other 21 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Claude Opus 4.1 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| 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
DeepSeek V4.1 Flash 1017 costs less
Repository review
50K input + 3K output tokens
DeepSeek V4.1 Flash 1017 costs less
Agent loop
200K input + 10K output tokens
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.
| Specification | Anthropic Claude Opus 4.1 | DeepSeek V4.1 Flash 1017 |
|---|---|---|
| Maker | Anthropic | DeepSeek |
| Weights | No public weights listed | Open weights |
| Released | August 5, 2025 | October 17, 2026 |
| Context window | 200K | 1.05M |
| Input $/Mtok | $15.00 | $0.15 |
| Output $/Mtok | $75.00 | $0.60 |
| Coding index | Not benchmarked | 70.3 |
| Independent measurements behind it | 1 | 4 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Claude Opus 4.1 better than DeepSeek V4.1 Flash 1017 for coding?
Only DeepSeek V4.1 Flash 1017 has a coding score, 70.3 on the Vibe Coding Index; Claude Opus 4.1 has none, so the two cannot be ranked on coding. Compare them on price, context and the boards below.
Which is cheaper, Claude Opus 4.1 or DeepSeek V4.1 Flash 1017?
Claude Opus 4.1 costs $15.00 per million input tokens and $75.00 per million output tokens; DeepSeek V4.1 Flash 1017 costs $0.15 and $0.60. Cost per solved task is known for neither of them.
Which has the bigger context window, Claude Opus 4.1 or DeepSeek V4.1 Flash 1017?
DeepSeek V4.1 Flash 1017, with 1.05M tokens against 200K.
How many benchmarks is the Claude Opus 4.1 vs DeepSeek V4.1 Flash 1017 comparison based on?
15 benchmarks have a result for both models as of October 22, 2026. Claude Opus 4.1's coding index rests on 1 independent benchmark and DeepSeek V4.1 Flash 1017's on 4. Where only one model has a result, the page says so instead of naming a winner.