DeepSeek V4.1 Flash vs o3
DeepSeek V4.1 Flash leads o3 on the Artificial Analysis Intelligence Index, 24.7 to 20.2, and DeepSeek V4.1 Flash costs 9.5x less per output token ($0.84 vs $8.00 per million). Updated October 22, 2026; 60 benchmarks have a result for both.
vs boards won of 60 shared
DeepSeek V4.1 Flash or o3: which to pick
Only DeepSeek V4.1 Flash has a coding score, 62.5 on the Vibe Coding Index; o3 has none, so the two cannot be ranked on coding.
Pick o3 for work measured by LegalBench (Vals AI) or MedCode (Vals AI), where it leads.
Model ADeepSeek V4.1 FlashDeepSeek62.5/1005 independent benchmarksNo cost per solved taskModel Bo3OpenAINot benchmarkedNo coding benchmark$0.571 per solved task
- Shared results
- 60
- DeepSeek V4.1 Flash only
- 41
- o3 only
- 42
- Like-for-like categories
- 7 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 has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
DeepSeek V4.1 Flash
DeepSeek V4.1 Flash leads, 24.7 against 20.2.
Same board, both measured
Reasoning
GPQA Diamond
No call
Only o3 has a GPQA Diamond result, 84.1%.
Directional only
Math
AIME
No call
Only o3 has a AIME result, 85.3%.
Directional only
Knowledge
MMLU Pro
No call
Only o3 has a MMLU Pro result, 85.6%.
Directional only
Web design
Design Arena: websites
DeepSeek V4.1 Flash
DeepSeek V4.1 Flash leads, 1308 against 1036.
Same board, both measured
Long documents
Listed context window
DeepSeek V4.1 Flash
DeepSeek V4.1 Flash takes 1.05M tokens against 200K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
DeepSeek V4.1 Flash
DeepSeek V4.1 Flash $0.0006, o3 $0.0060 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only o3 has the number, $0.571.
Directional only
At a glance
- Coding index
- DeepSeek V4.1 Flash 62.5 from 5 benchmarks, o3 not benchmarked.
- Widest category
- Web design, 31.4 points apart on average over 5 shared benchmarks.
- Widest single gap
- ARC-AGI-2: DeepSeek V4.1 Flash 72.9% against o3 6.5%, 66.4 points apart on a 0 to 100 scale.
- Output price
- DeepSeek V4.1 Flash $0.84 against o3 $8.00 per million output tokens, 9.5x apart.
- Context window
- DeepSeek V4.1 Flash takes 1.05M tokens, o3 200K.
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 | DeepSeek V4.1 Flash | Bars | o3 | Ties |
|---|---|---|---|---|
| Coding | 3 | 0 | ||
| Intelligence | 2 | 0 | ||
| Reasoning | 11 | 0 | ||
| Math | 4 | 0 | ||
| Knowledge | 4 | 3 | ||
| Web design | 5 | 0 | ||
| General | 28 | 0 | ||
| All shared boards | 57 | 3 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index30
| Benchmark | DeepSeek V4.1 Flash | o3 | Leader |
|---|---|---|---|
| Aider polyglot | Not measured | 81.3% | Only o3 measured |
| SWE-bench Verified | Not measured | 58.4% | Only o3 measured |
| SWE-bench Multimodal | Not measured | 36.0% | Only o3 measured |
| LiveBench coding | 90.2% | Not measured | Only DeepSeek V4.1 Flash measured |
| LMArena WebDev | 1618 | Not measured | Only DeepSeek V4.1 Flash measured |
| LiveCodeBench (Vals AI) | Not measured | 83.9% | Only o3 measured |
| Terminal-Bench 4 (Vals AI) | 19.7% | Not measured | Only DeepSeek V4.1 Flash measured |
| Vibe Code Bench (Vals AI) | 84.7% | Not measured | Only DeepSeek V4.1 Flash measured |
| Code migration (Vals AI) | 45.6% | Not measured | Only DeepSeek V4.1 Flash measured |
| ProgramBench (Vals AI) | 0.5% | Not measured | Only DeepSeek V4.1 Flash measured |
| IOI (Vals AI) | 40.3% | Not measured | Only DeepSeek V4.1 Flash measured |
| Terminal-Bench 2.1 (Vals AI) | 74.5% | Not measured | Only DeepSeek V4.1 Flash measured |
| SWE-bench Multimodal (Vals AI) | 46.5% | Not measured | Only DeepSeek V4.1 Flash measured |
| Vibe Code Bench 1-100 (Vals AI) | 16.4% | Not measured | Only DeepSeek V4.1 Flash measured |
| SkillsBench (Vals AI) | 69.8% | Not measured | Only DeepSeek V4.1 Flash measured |
| CyberBench (Vals AI) | 73.7% | Not measured | Only DeepSeek V4.1 Flash measured |
| LiveCodeBench (Artificial Analysis run) | Not measured | 80.8% | Only o3 measured |
| SciCode | 51.9% | Not measured | Only DeepSeek V4.1 Flash measured |
| Terminal-Bench Hard (Artificial Analysis run) | Not measured | 37.1% | Only o3 measured |
| FrontierCode | 43.9% | Not measured | Only DeepSeek V4.1 Flash measured |
| GSO-Bench | Not measured | 8.8% | Only o3 measured |
| WeirdML | Not measured | 52.4% | Only o3 measured |
| ALE-Bench | 1092.3 | 933.5 | DeepSeek V4.1 Flash |
| LMArena Text: coding | 1502 | 1407 | DeepSeek V4.1 Flash |
| LMArena Text: software and IT | 1496 | 1415 | DeepSeek V4.1 Flash |
| LMArena WebDev: React | 1628 | Not measured | Only DeepSeek V4.1 Flash measured |
| LMArena WebDev: HTML | 1612 | Not measured | Only DeepSeek V4.1 Flash measured |
| LMArena WebDev: from an image | 1606 | Not measured | Only DeepSeek V4.1 Flash measured |
| SciCode | Not measured | 9.2% | Only o3 measured |
| Neither model has a result on the other 10 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | DeepSeek V4.1 Flash | o3 | Leader |
|---|---|---|---|
| AA Intelligence Index | 24.7 | 20.2 | DeepSeek V4.1 Flash |
| Epoch Capabilities Index | 155.9 | 146.7 | DeepSeek V4.1 Flash |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index19 boards, none shared
| Benchmark | DeepSeek V4.1 Flash | o3 | Leader |
|---|---|---|---|
| LiveBench research | 86.8% | Not measured | Only DeepSeek V4.1 Flash measured |
| LiveBench browser | 84.0% | Not measured | Only DeepSeek V4.1 Flash measured |
| LiveBench long agentic | 40.1% | Not measured | Only DeepSeek V4.1 Flash measured |
| SREBench (Vals AI) | 0.8% | Not measured | Only DeepSeek V4.1 Flash measured |
| Finance Agent (Vals AI) | 53.5% | Not measured | Only DeepSeek V4.1 Flash measured |
| Tax Agent Bench (Vals AI) | 26.6% | Not measured | Only DeepSeek V4.1 Flash measured |
| Legal Research Bench (Vals AI) | 41.4% | Not measured | Only DeepSeek V4.1 Flash measured |
| Excel Modeling Benchmark (Vals AI) | 57.2% | Not measured | Only DeepSeek V4.1 Flash measured |
| BioMysteryBench (Vals AI) | 67.8% | Not measured | Only DeepSeek V4.1 Flash measured |
| Terminal-Bench-Science (Vals AI) | 0.0% | Not measured | Only DeepSeek V4.1 Flash measured |
| Vals Science Index | 29.6% | Not measured | Only DeepSeek V4.1 Flash measured |
| τ²-Bench Telecom | Not measured | 80.7% | Only o3 measured |
| APEX-Agents | 39.5% | Not measured | Only DeepSeek V4.1 Flash measured |
| METR time horizons | Not measured | 65.4% | Only o3 measured |
| GDPval | Not measured | 30.8% | Only o3 measured |
| DeepResearch Bench | Not measured | 45.2% | Only o3 measured |
| OSWorld | Not measured | 23.0% | Only o3 measured |
| Berkeley Function Calling Leaderboard (BFCL) | Not measured | 63.0% | Only o3 measured |
| BrowseComp-Plus | Not measured | 65.9% | Only o3 measured |
| Neither model has a result on the other 22 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index110
| Benchmark | DeepSeek V4.1 Flash | o3 | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 84.1% | Only o3 measured |
| LiveBench reasoning | 86.7% | Not measured | Only DeepSeek V4.1 Flash measured |
| MysteryMechanism (Vals AI) | 21.2% | Not measured | Only DeepSeek V4.1 Flash measured |
| MMMU Pro (Vals AI) | Not measured | 80.4% | Only o3 measured |
| GPQA Diamond (Artificial Analysis run) | Not measured | 82.7% | Only o3 measured |
| Humanity's Last Exam (Artificial Analysis run) | 39.2% | 20.1% | DeepSeek V4.1 Flash |
| GPQA Diamond (Epoch AI run) | 89.8% | 81.8% | DeepSeek V4.1 Flash |
| ARC-AGI | 94.5% | 60.8% | DeepSeek V4.1 Flash |
| ARC-AGI-2 | 72.9% | 6.5% | DeepSeek V4.1 Flash |
| SimpleBench | Not measured | 53.1% | Only o3 measured |
| Chess puzzles | 48.0% | 37.0% | DeepSeek V4.1 Flash |
| Mystery game puzzles | 43.0% | 29.0% | DeepSeek V4.1 Flash |
| VPCT | Not measured | 52.0% | Only o3 measured |
| LMArena Text: hard prompts | 1483 | 1402 | DeepSeek V4.1 Flash |
| LMArena Text: expert | 1501 | 1402 | DeepSeek V4.1 Flash |
| LMArena Text: hard prompts in English | 1488 | 1411 | DeepSeek V4.1 Flash |
| LMArena Vision: diagrams | 1297 | 1220 | DeepSeek V4.1 Flash |
| LMArena Vision: homework | 1307 | 1234 | DeepSeek V4.1 Flash |
| Kagi LLM Benchmark | Not measured | 67.6% | Only o3 measured |
| Neither model has a result on the other 3 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | DeepSeek V4.1 Flash | o3 | Leader |
|---|---|---|---|
| AIME | Not measured | 85.3% | Only o3 measured |
| MATH 500 (Vals AI) | Not measured | 94.6% | Only o3 measured |
| MGSM (Vals AI) | Not measured | 91.8% | Only o3 measured |
| AA Math Index | Not measured | 88.3 | Only o3 measured |
| AIME 2025 (Artificial Analysis run) | Not measured | 88.3% | Only o3 measured |
| OTIS Mock AIME | 98.3% | 84.4% | DeepSeek V4.1 Flash |
| FrontierMath, tiers 1 to 3 | 67.4% | 33.3% | DeepSeek V4.1 Flash |
| FrontierMath, tier 4 | 26.8% | Not measured | Only DeepSeek V4.1 Flash measured |
| ProofBench | 54.0% | Not measured | Only DeepSeek V4.1 Flash measured |
| MATH level 5 | Not measured | 97.8% | Only o3 measured |
| LMArena Text: math | 1478 | 1426 | DeepSeek V4.1 Flash |
| LMArena Text: mathematical work | 1485 | 1423 | DeepSeek V4.1 Flash |
| Neither model has a result on the other 1 board here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index43
| Benchmark | DeepSeek V4.1 Flash | o3 | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 85.6% | Only o3 measured |
| LegalBench (Vals AI) | 83.3% | 83.8% | o3 |
| CorpFin (Vals AI) | Not measured | 59.7% | Only o3 measured |
| TaxEval (Vals AI) | Not measured | 74.6% | Only o3 measured |
| MortgageTax (Vals AI) | Not measured | 65.7% | Only o3 measured |
| MedQA (Vals AI) | Not measured | 96.1% | Only o3 measured |
| MedCode (Vals AI) | 41.2% | 47.3% | o3 |
| MMLU Pro (Artificial Analysis run) | Not measured | 85.3% | Only o3 measured |
| SimpleQA Verified | 42.9% | 49.4% | o3 |
| GeoBench | Not measured | 74.0% | Only o3 measured |
| LMArena Text: science | 1469 | 1429 | DeepSeek V4.1 Flash |
| LMArena Text: medicine and healthcare | 1484 | 1448 | DeepSeek V4.1 Flash |
| LMArena Text: legal and government | 1443 | 1428 | DeepSeek V4.1 Flash |
| LMArena Text: business and finance | 1461 | 1393 | DeepSeek V4.1 Flash |
| FACTS Benchmark Suite | Not measured | 44.4% | Only o3 measured |
| Neither model has a result on the other 3 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | DeepSeek V4.1 Flash | o3 | Leader |
|---|---|---|---|
| Design Arena: websites | 1308 | 1036 | DeepSeek V4.1 Flash |
| Design Arena: UI components | 1312 | 1017 | DeepSeek V4.1 Flash |
| Design Arena: game dev | 1330 | 1034 | DeepSeek V4.1 Flash |
| Design Arena: data viz | 1291 | 1200 | DeepSeek V4.1 Flash |
| Design Arena: 3D | 1355 | Not measured | Only DeepSeek V4.1 Flash measured |
| Design Arena: all code categories | 1320 | 1020 | DeepSeek V4.1 Flash |
| Design Arena: SVG | 1245 | Not measured | Only DeepSeek V4.1 Flash measured |
| Design Arena: ASCII art | 1265 | Not measured | Only DeepSeek V4.1 Flash measured |
| LiveBench design | 79.2% | Not measured | Only DeepSeek V4.1 Flash measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index280
| Benchmark | DeepSeek V4.1 Flash | o3 | Leader |
|---|---|---|---|
| LiveBench data analysis | 79.3% | Not measured | Only DeepSeek V4.1 Flash measured |
| Public Benefits Bench (Vals AI) | 64.3% | Not measured | Only DeepSeek V4.1 Flash measured |
| SAGE (Vals AI) | 47.9% | 41.8% | DeepSeek V4.1 Flash |
| MedScribe (Vals AI) | 85.5% | 76.7% | DeepSeek V4.1 Flash |
| IFBench | Not measured | 71.4% | Only o3 measured |
| Long context reasoning (AA-LCR) | 84.0% | 74.7% | DeepSeek V4.1 Flash |
| DTBench | 89.9% | 84.8% | DeepSeek V4.1 Flash |
| LMCA | 47.0% | 39.7% | DeepSeek V4.1 Flash |
| Fiction.LiveBench | Not measured | 88.9% | Only o3 measured |
| Creative writing (Lech Mazur) | Not measured | 83.9% | Only o3 measured |
| CL-bench | Not measured | 17.8% | Only o3 measured |
| Surface Evolver Bench | 46.3% | Not measured | Only DeepSeek V4.1 Flash measured |
| Furniture assembly | 34.2% | Not measured | Only DeepSeek V4.1 Flash measured |
| LMArena Text | 1464 | 1410 | DeepSeek V4.1 Flash |
| LMArena Text: instruction following | 1473 | 1368 | DeepSeek V4.1 Flash |
| LMArena Text: creative writing | 1437 | 1359 | DeepSeek V4.1 Flash |
| LMArena Vision | 1278 | 1214 | DeepSeek V4.1 Flash |
| LMArena Text: English | 1473 | 1417 | DeepSeek V4.1 Flash |
| LMArena Text: non-English | 1449 | 1401 | DeepSeek V4.1 Flash |
| LMArena Text: Chinese | 1501 | 1437 | DeepSeek V4.1 Flash |
| LMArena Text: German | 1470 | 1420 | DeepSeek V4.1 Flash |
| LMArena Text: Japanese | 1432 | 1403 | DeepSeek V4.1 Flash |
| LMArena Text: Korean | 1436 | 1370 | DeepSeek V4.1 Flash |
| LMArena Text: French | 1465 | 1430 | DeepSeek V4.1 Flash |
| LMArena Text: Spanish | 1459 | 1395 | DeepSeek V4.1 Flash |
| LMArena Text: Russian | 1467 | 1406 | DeepSeek V4.1 Flash |
| LMArena Text: Polish | 1457 | 1438 | DeepSeek V4.1 Flash |
| LMArena Text: multi-turn | 1461 | 1405 | DeepSeek V4.1 Flash |
| LMArena Text: longer queries | 1473 | 1372 | DeepSeek V4.1 Flash |
| LMArena Text: writing and language | 1450 | 1372 | DeepSeek V4.1 Flash |
| LMArena Text: entertainment and media | 1445 | 1373 | DeepSeek V4.1 Flash |
| LMArena Vision: English | 1288 | 1221 | DeepSeek V4.1 Flash |
| LMArena Vision: Chinese | 1327 | 1237 | DeepSeek V4.1 Flash |
| LMArena Vision: reading text | 1282 | 1218 | DeepSeek V4.1 Flash |
| LMArena Vision: humor | 1260 | 1222 | DeepSeek V4.1 Flash |
| LMArena Vision: captioning | Not measured | 1210 | Only o3 measured |
| LMArena Vision: recognizing things | Not measured | 1234 | Only o3 measured |
| LMArena Vision: creative writing | 1275 | 1201 | DeepSeek V4.1 Flash |
| Neither model has a result on the other 8 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | DeepSeek V4.1 Flash | o3 | 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$0.0006Fits in one request
o3$0.0060Fits in one request
DeepSeek V4.1 Flash costs less
Repository review
50K input + 3K output tokens
DeepSeek V4.1 Flash$0.014Fits in one request
o3$0.124Fits in one request
DeepSeek V4.1 Flash costs less
Agent loop
200K input + 10K output tokens
DeepSeek V4.1 Flash$0.053Fits in one request
o3$0.480Exceeds the context window
DeepSeek V4.1 Flash 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 | DeepSeek V4.1 Flash | OpenAI o3 |
|---|---|---|
| Maker | DeepSeek | OpenAI |
| Weights | Open weights | No public weights listed |
| Released | September 10, 2026 | April 16, 2025 |
| Context window | 1.05M | 200K |
| Input $/Mtok | $0.2225 | $2.00 |
| Output $/Mtok | $0.84 | $8.00 |
| Coding index | 62.5 | Not benchmarked |
| Independent measurements behind it | 5 | 0 |
| Cost per solved task | Not computable | $0.571 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is DeepSeek V4.1 Flash better than o3 for coding?
Only DeepSeek V4.1 Flash has a coding score, 62.5 on the Vibe Coding Index; o3 has none, so the two cannot be ranked on coding. Pick o3 for work measured by LegalBench (Vals AI) or MedCode (Vals AI), where it leads.
Which is cheaper, DeepSeek V4.1 Flash or o3?
DeepSeek V4.1 Flash costs $0.2225 per million input tokens and $0.84 per million output tokens; o3 costs $2.00 and $8.00. Cost per solved task is known for o3 only.
Which has the bigger context window, DeepSeek V4.1 Flash or o3?
DeepSeek V4.1 Flash, with 1.05M tokens against 200K.
How many benchmarks is the DeepSeek V4.1 Flash vs o3 comparison based on?
60 benchmarks have a result for both models as of October 22, 2026. DeepSeek V4.1 Flash's coding index rests on 5 independent benchmarks and o3's on 0. Where only one model has a result, the page says so instead of naming a winner.