DeepSeek V3 vs DeepSeek V4.1 Flash 1017
Updated October 21, 2026. 6 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
Decision reading
DeepSeek V3 scores 70.2 and DeepSeek V4.1 Flash 1017 83.3 on the Vibe Coding Index, but no coding benchmark measured both, so the gap is directional, not a ranking.
Pick DeepSeek V4.1 Flash 1017 when output tokens cost 1.7x less, or when the context window is larger, 1.05M against 164K tokens.
- Shared results
- 6
- DeepSeek V3 only
- 7
- DeepSeek V4.1 Flash 1017 only
- 26
- Like-for-like categories
- 1 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.
Coding
Vibe Coding Index, four public coding benchmarks
No call
70.2 against 83.3, from different benchmarks with none in common.
Directional only
Intelligence
AA Intelligence Index
No call
Only DeepSeek V4.1 Flash 1017 has a AA Intelligence Index result, 39.5.
Directional only
Web design
Design Arena: websites
DeepSeek V4.1 Flash 1017
DeepSeek V4.1 Flash 1017 leads, 1312 against 1120.
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 164K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
DeepSeek V4.1 Flash 1017
DeepSeek V3 $0.0008, DeepSeek V4.1 Flash 1017 $0.0004 per turn.
List prices
At a glance
- Coding index
- DeepSeek V3 70.2 from 1 benchmark, DeepSeek V4.1 Flash 1017 83.3 from 2 benchmarks.
- Widest category
- Web design, 30.5 points apart on average over 6 shared benchmarks.
- Widest single gap
- Design Arena: game dev: DeepSeek V3 1054 against DeepSeek V4.1 Flash 1017 1365, 38.9 points apart on a 0 to 100 scale.
- Output price
- DeepSeek V3 $1.0287 against DeepSeek V4.1 Flash 1017 $0.60 per million output tokens, 1.7x apart.
- Context window
- DeepSeek V3 takes 164K 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 | DeepSeek V3 | Bars | DeepSeek V4.1 Flash 1017 | Ties |
|---|---|---|---|---|
| Web design | 0 | 6 | ||
| All shared boards | 0 | 6 |
CodingDirectional onlyFour of these boards feed the Vibe Coding Index11 boards, none shared
| Benchmark | DeepSeek V3 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| Aider polyglot | 70.2% | Not measured | Only DeepSeek V3 measured |
| SWE-bench Lite | 30.7% | Not measured | Only DeepSeek V3 measured |
| LiveBench coding | Not measured | 96.0% | Only DeepSeek V4.1 Flash 1017 measured |
| LMArena WebDev | Not measured | 1664 | Only DeepSeek V4.1 Flash 1017 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 |
| ALE-Bench | Not measured | 1622.0 | Only DeepSeek V4.1 Flash 1017 measured |
| LMArena WebDev: React | Not measured | 1667 | Only DeepSeek V4.1 Flash 1017 measured |
| LMArena WebDev: HTML | Not measured | 1687 | Only DeepSeek V4.1 Flash 1017 measured |
| Neither model has a result on the other 27 boards here | |||
IntelligenceDirectional onlyPublic boards, shown as published, kept out of the index1 board, none shared
| Benchmark | DeepSeek V3 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| AA Intelligence Index | Not measured | 39.5 | Only DeepSeek V4.1 Flash 1017 measured |
| Neither model has a result on the other 1 board here | |||
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index9 boards, none shared
| Benchmark | DeepSeek V3 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| Design Arena: spreadsheets | Not measured | 1238 | 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 |
| Neither model has a result on the other 30 boards here | |||
ReasoningDirectional onlyPublic boards, shown as published, kept out of the index3 boards, none shared
| Benchmark | DeepSeek V3 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| LiveBench reasoning | Not measured | 89.1% | Only DeepSeek V4.1 Flash 1017 measured |
| Humanity's Last Exam (Artificial Analysis run) | Not measured | 43.3% | Only DeepSeek V4.1 Flash 1017 measured |
| GPQA Diamond (Epoch AI run) | 71.2% | Not measured | Only DeepSeek V3 measured |
| Neither model has a result on the other 18 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index1 board, none shared
| Benchmark | DeepSeek V3 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| OTIS Mock AIME | 48.9% | Not measured | Only DeepSeek V3 measured |
| Neither model has a result on the other 12 boards here | |||
KnowledgeNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | DeepSeek V3 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| Neither model has a result on 17 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index06
| Benchmark | DeepSeek V3 | DeepSeek V4.1 Flash 1017 | Leader |
|---|---|---|---|
| Design Arena: websites | 1120 | 1312 | DeepSeek V4.1 Flash 1017 |
| Design Arena: UI components | 1093 | 1305 | DeepSeek V4.1 Flash 1017 |
| Design Arena: game dev | 1054 | 1365 | DeepSeek V4.1 Flash 1017 |
| Design Arena: data viz | 1089 | 1330 | DeepSeek V4.1 Flash 1017 |
| Design Arena: 3D | 1087 | 1368 | DeepSeek V4.1 Flash 1017 |
| Design Arena: all code categories | 1108 | 1335 | DeepSeek V4.1 Flash 1017 |
| Design Arena: SVG | 976 | Not measured | Only DeepSeek V3 measured |
| Design Arena: ASCII art | Not measured | 1244 | Only DeepSeek V4.1 Flash 1017 measured |
| LiveBench design | Not measured | 83.4% | Only DeepSeek V4.1 Flash 1017 measured |
GeneralDirectional onlyPublic boards, shown as published, kept out of the index5 boards, none shared
| Benchmark | DeepSeek V3 | 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 |
| Long context reasoning (AA-LCR) | Not measured | 82.7% | Only DeepSeek V4.1 Flash 1017 measured |
| DTBench | 62.7% | Not measured | Only DeepSeek V3 measured |
| LMCA | 15.2% | Not measured | Only DeepSeek V3 measured |
| Neither model has a result on the other 41 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | DeepSeek V3 | 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 | DeepSeek V3 | DeepSeek V4.1 Flash 1017 |
|---|---|---|
| Maker | DeepSeek | DeepSeek |
| Weights | Open weights | Open weights |
| Released | December 26, 2024 | October 17, 2026 |
| Context window | 164K | 1.05M |
| Input $/Mtok | $0.2574 | $0.15 |
| Output $/Mtok | $1.0287 | $0.60 |
| Coding index | 70.2 | 83.3 |
| Independent measurements behind it | 1 | 2 |
| Cost per solved task | Not computable | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is DeepSeek V3 better than DeepSeek V4.1 Flash 1017 for coding?
DeepSeek V3 scores 70.2 and DeepSeek V4.1 Flash 1017 83.3 on the Vibe Coding Index, but no coding benchmark measured both, so the gap is directional, not a ranking. Pick DeepSeek V4.1 Flash 1017 when output tokens cost 1.7x less, or when the context window is larger, 1.05M against 164K tokens.
Which is cheaper, DeepSeek V3 or DeepSeek V4.1 Flash 1017?
DeepSeek V3 costs $0.2574 per million input tokens and $1.0287 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, DeepSeek V3 or DeepSeek V4.1 Flash 1017?
DeepSeek V4.1 Flash 1017, with 1.05M tokens against 164K.
How many benchmarks is the DeepSeek V3 vs DeepSeek V4.1 Flash 1017 comparison based on?
6 benchmarks have a result for both models as of October 21, 2026. DeepSeek V3's coding index rests on 1 independent benchmark 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.