DeepSeek V4 Flash 0731 vs Gemini 3.1 Pro Preview
DeepSeek V4 Flash 0731 leads Gemini 3.1 Pro Preview on coding, 51.8 to 32.3 on the Vibe Coding Index, and DeepSeek V4 Flash 0731 costs 42.9x less per output token ($0.28 vs $12.00 per million). Updated October 21, 2026; 51 benchmarks have a result for both.
vs boards won of 51 shared, 2 tied
DeepSeek V4 Flash 0731 or Gemini 3.1 Pro Preview: which to pick
Pick DeepSeek V4 Flash 0731 for coding: it scores 51.8 on the Vibe Coding Index against 32.3 for Gemini 3.1 Pro Preview.
Pick Gemini 3.1 Pro Preview for work measured by LiveCodeBench (Vals AI) or IOI (Vals AI), where it leads.
Model ADeepSeek V4 Flash 0731DeepSeek51.8/1004 independent benchmarks$0.01 per solved taskModel BGemini 3.1 Pro PreviewGoogle32.3/1004 independent benchmarks$0.99 per solved task
- Shared results
- 51
- DeepSeek V4 Flash 0731 only
- 4
- Gemini 3.1 Pro Preview only
- 82
- Like-for-like categories
- 8 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
DeepSeek V4 Flash 0731
DeepSeek V4 Flash 0731 scores 51.8 against 32.3.
4 benchmarks behind each score
Intelligence
AA Intelligence Index
DeepSeek V4 Flash 0731
DeepSeek V4 Flash 0731 leads, 34.3 against 29.7.
Same board, both measured
Agentic work
AA Agentic Index
DeepSeek V4 Flash 0731
DeepSeek V4 Flash 0731 leads, 41.0 against 8.2.
Same board, both measured
Reasoning
GPQA Diamond
Gemini 3.1 Pro Preview
Gemini 3.1 Pro Preview leads, 95.5% against 89.9%.
Same board, both measured
Math
AIME
No call
Only Gemini 3.1 Pro Preview has a AIME result, 98.1%.
Directional only
Knowledge
MMLU Pro
Gemini 3.1 Pro Preview
Gemini 3.1 Pro Preview leads, 91.0% against 86.2%.
Same board, both measured
Web design
Design Arena: websites
DeepSeek V4 Flash 0731
DeepSeek V4 Flash 0731 leads, 1238 against 1234.
Same board, both measured
Long documents
Listed context window
No call
Both take 1.05M tokens.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
DeepSeek V4 Flash 0731
DeepSeek V4 Flash 0731 $0.0003, Gemini 3.1 Pro Preview $0.0080 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
DeepSeek V4 Flash 0731
DeepSeek V4 Flash 0731 $0.01, Gemini 3.1 Pro Preview $0.99.
Published attempt cost and pass rate
At a glance
- Coding index
- DeepSeek V4 Flash 0731 51.8 from 4 benchmarks, Gemini 3.1 Pro Preview 32.3 from 4 benchmarks.
- Widest category
- Knowledge, 12.8 points apart on average over 6 shared benchmarks.
- Widest single gap
- Vibe Code Bench (Vals AI): DeepSeek V4 Flash 0731 74.7% against Gemini 3.1 Pro Preview 32.0%, 42.7 points apart on a 0 to 100 scale.
- Output price
- DeepSeek V4 Flash 0731 $0.28 against Gemini 3.1 Pro Preview $12.00 per million output tokens, 42.9x apart.
- Context window
- Both take 1.05M tokens.
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 Flash 0731 | Bars | Gemini 3.1 Pro Preview | Ties |
|---|---|---|---|---|
| Coding | 6 | 5 | 1 tie | |
| Intelligence | 1 | 0 | ||
| Agentic work | 7 | 0 | ||
| Reasoning | 0 | 8 | 1 tie | |
| Math | 1 | 3 | ||
| Knowledge | 0 | 6 | ||
| Web design | 3 | 5 | ||
| General | 1 | 3 | ||
| All shared boards | 19 | 30 | 2 ties |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index65
| Benchmark | DeepSeek V4 Flash 0731 | Gemini 3.1 Pro Preview | Leader |
|---|---|---|---|
| LMArena WebDev | Not measured | 1447 | Only Gemini 3.1 Pro Preview measured |
| AA Coding Index | 69.1 | 68.8 | DeepSeek V4 Flash 0731 |
| LiveCodeBench (Vals AI) | 87.3% | 88.5% | Gemini 3.1 Pro Preview |
| SWE-bench Verified (Vals AI) | 88.8% | 78.8% | DeepSeek V4 Flash 0731 |
| Terminal-Bench 4 (Vals AI) | 18.7% | 2.5% | DeepSeek V4 Flash 0731 |
| Vibe Code Bench (Vals AI) | 74.7% | 32.0% | DeepSeek V4 Flash 0731 |
| Code migration (Vals AI) | 38.6% | 17.3% | DeepSeek V4 Flash 0731 |
| ProgramBench (Vals AI) | 0.0% | 0.0% | Tie |
| IOI (Vals AI) | 32.7% | 51.8% | Gemini 3.1 Pro Preview |
| Terminal-Bench 2.1 (Vals AI) | 67.0% | 70.8% | Gemini 3.1 Pro Preview |
| Vibe Code Bench 1-100 (Vals AI) | Not measured | 6.7% | Only Gemini 3.1 Pro Preview measured |
| SkillsBench (Vals AI) | 50.7% | Not measured | Only DeepSeek V4 Flash 0731 measured |
| CyberBench (Vals AI) | 72.1% | Not measured | Only DeepSeek V4 Flash 0731 measured |
| SciCode | 50.3% | 58.7% | Gemini 3.1 Pro Preview |
| Terminal-Bench Hard (Artificial Analysis run) | Not measured | 53.8% | Only Gemini 3.1 Pro Preview measured |
| Terminal-Bench | Not measured | 80.2% | Only Gemini 3.1 Pro Preview measured |
| FrontierCode | 18.8% | Not measured | Only DeepSeek V4 Flash 0731 measured |
| GSO-Bench | Not measured | 22.6% | Only Gemini 3.1 Pro Preview measured |
| WeirdML | 63.0% | 72.1% | Gemini 3.1 Pro Preview |
| MirrorCode | Not measured | 8.9% | Only Gemini 3.1 Pro Preview measured |
| ALE-Bench | 1306.1 | 1160.6 | DeepSeek V4 Flash 0731 |
| LMArena Text: coding | Not measured | 1484 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: software and IT | Not measured | 1487 | Only Gemini 3.1 Pro Preview measured |
| LMArena WebDev: React | Not measured | 1438 | Only Gemini 3.1 Pro Preview measured |
| LMArena WebDev: HTML | Not measured | 1490 | Only Gemini 3.1 Pro Preview measured |
| LMArena WebDev: from an image | Not measured | 1481 | Only Gemini 3.1 Pro Preview measured |
| SciCode | Not measured | 14.3% | Only Gemini 3.1 Pro Preview measured |
| Neither model has a result on the other 12 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | DeepSeek V4 Flash 0731 | Gemini 3.1 Pro Preview | Leader |
|---|---|---|---|
| AA Intelligence Index | 34.3 | 29.7 | DeepSeek V4 Flash 0731 |
| Epoch Capabilities Index | 154.8 | Not measured | Only DeepSeek V4 Flash 0731 measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index70
| Benchmark | DeepSeek V4 Flash 0731 | Gemini 3.1 Pro Preview | Leader |
|---|---|---|---|
| AA Agentic Index | 41.0 | 8.2 | DeepSeek V4 Flash 0731 |
| Design Arena: agents building web apps | Not measured | 1125 | Only Gemini 3.1 Pro Preview measured |
| Design Arena: agents building full-stack apps | Not measured | 1068 | Only Gemini 3.1 Pro Preview measured |
| Design Arena: agents building mobile apps | Not measured | 1093 | Only Gemini 3.1 Pro Preview measured |
| Design Arena: agents building Android apps | Not measured | 1048 | Only Gemini 3.1 Pro Preview measured |
| Design Arena: agents building Godot games | Not measured | 1236 | Only Gemini 3.1 Pro Preview measured |
| Design Arena: agents building games | Not measured | 1114 | Only Gemini 3.1 Pro Preview measured |
| Design Arena: HTML slides | Not measured | 1153 | Only Gemini 3.1 Pro Preview measured |
| Design Arena: PowerPoint slides | Not measured | 1066 | Only Gemini 3.1 Pro Preview measured |
| SREBench (Vals AI) | Not measured | 0.0% | Only Gemini 3.1 Pro Preview measured |
| Finance Agent (Vals AI) | 49.5% | 43.0% | DeepSeek V4 Flash 0731 |
| Tax Agent Bench (Vals AI) | 28.1% | 9.3% | DeepSeek V4 Flash 0731 |
| Legal Research Bench (Vals AI) | 30.3% | 20.7% | DeepSeek V4 Flash 0731 |
| Excel Modeling Benchmark (Vals AI) | 57.0% | 52.6% | DeepSeek V4 Flash 0731 |
| BioMysteryBench (Vals AI) | 64.4% | 60.0% | DeepSeek V4 Flash 0731 |
| Terminal-Bench-Science (Vals AI) | 4.3% | 1.4% | DeepSeek V4 Flash 0731 |
| Vals Science Index | Not measured | 27.4% | Only Gemini 3.1 Pro Preview measured |
| τ²-Bench Telecom | Not measured | 95.6% | Only Gemini 3.1 Pro Preview measured |
| APEX-Agents | Not measured | 35.1% | Only Gemini 3.1 Pro Preview measured |
| METR time horizons | Not measured | 77.0% | Only Gemini 3.1 Pro Preview measured |
| BALROG | Not measured | 57.0% | Only Gemini 3.1 Pro Preview measured |
| DeepResearch Bench | Not measured | 47.8% | Only Gemini 3.1 Pro Preview measured |
| PostTrainBench | Not measured | 22.0% | Only Gemini 3.1 Pro Preview measured |
| Vending-Bench 2 | Not measured | $911 | Only Gemini 3.1 Pro Preview measured |
| Neither model has a result on the other 17 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index08
| Benchmark | DeepSeek V4 Flash 0731 | Gemini 3.1 Pro Preview | Leader |
|---|---|---|---|
| GPQA Diamond | 89.9% | 95.5% | Gemini 3.1 Pro Preview |
| MysteryMechanism (Vals AI) | Not measured | 20.7% | Only Gemini 3.1 Pro Preview measured |
| MMMU Pro (Vals AI) | Not measured | 88.2% | Only Gemini 3.1 Pro Preview measured |
| GPQA Diamond (Artificial Analysis run) | 90.8% | 94.1% | Gemini 3.1 Pro Preview |
| Humanity's Last Exam (Artificial Analysis run) | 38.6% | 47.0% | Gemini 3.1 Pro Preview |
| GPQA Diamond (Epoch AI run) | 91.0% | 94.4% | Gemini 3.1 Pro Preview |
| ARC-AGI | 89.0% | 98.0% | Gemini 3.1 Pro Preview |
| ARC-AGI-2 | 61.4% | 77.1% | Gemini 3.1 Pro Preview |
| SimpleBench | 61.1% | 79.6% | Gemini 3.1 Pro Preview |
| Chess puzzles | 32.0% | 51.0% | Gemini 3.1 Pro Preview |
| Mystery game puzzles | 34.0% | 34.0% | Tie |
| EBR-bench | Not measured | 14.3% | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: hard prompts | Not measured | 1485 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: expert | Not measured | 1483 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: hard prompts in English | Not measured | 1480 | Only Gemini 3.1 Pro Preview measured |
| LMArena Vision: diagrams | Not measured | 1311 | Only Gemini 3.1 Pro Preview measured |
| LMArena Vision: homework | Not measured | 1316 | Only Gemini 3.1 Pro Preview measured |
| Neither model has a result on the other 5 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index13
| Benchmark | DeepSeek V4 Flash 0731 | Gemini 3.1 Pro Preview | Leader |
|---|---|---|---|
| AIME | Not measured | 98.1% | Only Gemini 3.1 Pro Preview measured |
| OTIS Mock AIME | 94.4% | 95.6% | Gemini 3.1 Pro Preview |
| FrontierMath, tiers 1 to 3 | 57.5% | 59.6% | Gemini 3.1 Pro Preview |
| FrontierMath, tier 4 | 24.4% | 26.8% | Gemini 3.1 Pro Preview |
| ProofBench | 56.0% | 26.0% | DeepSeek V4 Flash 0731 |
| LMArena Text: math | Not measured | 1486 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: mathematical work | Not measured | 1478 | Only Gemini 3.1 Pro Preview measured |
| Neither model has a result on the other 6 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index06
| Benchmark | DeepSeek V4 Flash 0731 | Gemini 3.1 Pro Preview | Leader |
|---|---|---|---|
| MMLU Pro | 86.2% | 91.0% | Gemini 3.1 Pro Preview |
| LegalBench (Vals AI) | 77.7% | 87.4% | Gemini 3.1 Pro Preview |
| CaseLaw (Vals AI) | Not measured | 64.8% | Only Gemini 3.1 Pro Preview measured |
| CorpFin (Vals AI) | 61.9% | 64.5% | Gemini 3.1 Pro Preview |
| TaxEval (Vals AI) | 70.7% | 72.9% | Gemini 3.1 Pro Preview |
| MortgageTax (Vals AI) | Not measured | 69.4% | Only Gemini 3.1 Pro Preview measured |
| MedQA (Vals AI) | Not measured | 96.4% | Only Gemini 3.1 Pro Preview measured |
| MedCode (Vals AI) | 41.4% | 59.1% | Gemini 3.1 Pro Preview |
| SimpleQA Verified | 33.6% | 73.5% | Gemini 3.1 Pro Preview |
| LMArena Text: science | Not measured | 1497 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: medicine and healthcare | Not measured | 1486 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: legal and government | Not measured | 1487 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: business and finance | Not measured | 1459 | Only Gemini 3.1 Pro Preview measured |
| FACTS Benchmark Suite | Not measured | 67.4% | Only Gemini 3.1 Pro Preview measured |
| Neither model has a result on the other 4 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index35
| Benchmark | DeepSeek V4 Flash 0731 | Gemini 3.1 Pro Preview | Leader |
|---|---|---|---|
| Design Arena: websites | 1238 | 1234 | DeepSeek V4 Flash 0731 |
| Design Arena: UI components | 1235 | 1227 | DeepSeek V4 Flash 0731 |
| Design Arena: game dev | 1208 | 1203 | DeepSeek V4 Flash 0731 |
| Design Arena: data viz | 1180 | 1209 | Gemini 3.1 Pro Preview |
| Design Arena: 3D | 1209 | 1234 | Gemini 3.1 Pro Preview |
| Design Arena: all code categories | 1230 | 1231 | Gemini 3.1 Pro Preview |
| Design Arena: SVG | 1185 | 1285 | Gemini 3.1 Pro Preview |
| Design Arena: ASCII art | 1090 | 1270 | Gemini 3.1 Pro Preview |
| Neither model has a result on the other 1 board here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index13
| Benchmark | DeepSeek V4 Flash 0731 | Gemini 3.1 Pro Preview | Leader |
|---|---|---|---|
| Public Benefits Bench (Vals AI) | Not measured | 53.8% | Only Gemini 3.1 Pro Preview measured |
| SAGE (Vals AI) | Not measured | 48.7% | Only Gemini 3.1 Pro Preview measured |
| MedScribe (Vals AI) | 80.4% | 76.1% | DeepSeek V4 Flash 0731 |
| Vals Multimodal Index | Not measured | 56.1% | Only Gemini 3.1 Pro Preview measured |
| IFBench | Not measured | 77.1% | Only Gemini 3.1 Pro Preview measured |
| Long context reasoning (AA-LCR) | 79.7% | 82.0% | Gemini 3.1 Pro Preview |
| DTBench | 90.9% | 97.1% | Gemini 3.1 Pro Preview |
| LMCA | 41.7% | 53.8% | Gemini 3.1 Pro Preview |
| CL-bench | Not measured | 20.8% | Only Gemini 3.1 Pro Preview measured |
| Furniture assembly | Not measured | 26.7% | Only Gemini 3.1 Pro Preview measured |
| ExploitBench | Not measured | 26.1% | Only Gemini 3.1 Pro Preview measured |
| CL-bench Life | Not measured | 16.9% | Only Gemini 3.1 Pro Preview measured |
| LMArena Text | Not measured | 1480 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: instruction following | Not measured | 1466 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: creative writing | Not measured | 1482 | Only Gemini 3.1 Pro Preview measured |
| LMArena Vision | Not measured | 1296 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: English | Not measured | 1478 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: non-English | Not measured | 1476 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: Chinese | Not measured | 1527 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: German | Not measured | 1490 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: Japanese | Not measured | 1491 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: Korean | Not measured | 1455 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: French | Not measured | 1487 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: Spanish | Not measured | 1481 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: Russian | Not measured | 1497 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: Polish | Not measured | 1498 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: multi-turn | Not measured | 1487 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: longer queries | Not measured | 1482 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: writing and language | Not measured | 1481 | Only Gemini 3.1 Pro Preview measured |
| LMArena Text: entertainment and media | Not measured | 1465 | Only Gemini 3.1 Pro Preview measured |
| LMArena Vision: English | Not measured | 1287 | Only Gemini 3.1 Pro Preview measured |
| LMArena Vision: Chinese | Not measured | 1364 | Only Gemini 3.1 Pro Preview measured |
| LMArena Vision: reading text | Not measured | 1304 | Only Gemini 3.1 Pro Preview measured |
| LMArena Vision: humor | Not measured | 1322 | Only Gemini 3.1 Pro Preview measured |
| LMArena Vision: captioning | Not measured | 1345 | Only Gemini 3.1 Pro Preview measured |
| LMArena Vision: recognizing things | Not measured | 1330 | Only Gemini 3.1 Pro Preview measured |
| LMArena Vision: creative writing | Not measured | 1324 | Only Gemini 3.1 Pro Preview measured |
| LMArena Document | Not measured | 1444 | Only Gemini 3.1 Pro Preview measured |
| 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 Flash 0731 | Gemini 3.1 Pro Preview | 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 Flash 0731$0.0003Fits in one request
Gemini 3.1 Pro Preview$0.0080Fits in one request
DeepSeek V4 Flash 0731 costs less
Repository review
50K input + 3K output tokens
DeepSeek V4 Flash 0731$0.0078Fits in one request
Gemini 3.1 Pro Preview$0.136Fits in one request
DeepSeek V4 Flash 0731 costs less
Agent loop
200K input + 10K output tokens
DeepSeek V4 Flash 0731$0.031Fits in one request
Gemini 3.1 Pro Preview$0.520Fits in one request
DeepSeek V4 Flash 0731 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 Flash 0731 | Google Gemini 3.1 Pro Preview |
|---|---|---|
| Maker | DeepSeek | |
| Weights | Open weights | No public weights listed |
| Released | July 31, 2026 | February 19, 2026 |
| Context window | 1.05M | 1.05M |
| Input $/Mtok | $0.14 | $2.00 |
| Output $/Mtok | $0.28 | $12.00 |
| Coding index | 51.8 | 32.3 |
| Independent measurements behind it | 4 | 4 |
| Cost per solved task | $0.01 | $0.99 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is DeepSeek V4 Flash 0731 better than Gemini 3.1 Pro Preview for coding?
Pick DeepSeek V4 Flash 0731 for coding: it scores 51.8 on the Vibe Coding Index against 32.3 for Gemini 3.1 Pro Preview. Pick Gemini 3.1 Pro Preview for work measured by LiveCodeBench (Vals AI) or IOI (Vals AI), where it leads.
Which is cheaper, DeepSeek V4 Flash 0731 or Gemini 3.1 Pro Preview?
DeepSeek V4 Flash 0731 costs $0.14 per million input tokens and $0.28 per million output tokens; Gemini 3.1 Pro Preview costs $2.00 and $12.00. Per solved SWE-bench Verified task, DeepSeek V4 Flash 0731 costs $0.01 and Gemini 3.1 Pro Preview $0.99.
Which has the bigger context window, DeepSeek V4 Flash 0731 or Gemini 3.1 Pro Preview?
Neither: both take 1.05M tokens.
How many benchmarks is the DeepSeek V4 Flash 0731 vs Gemini 3.1 Pro Preview comparison based on?
51 benchmarks have a result for both models as of October 21, 2026. DeepSeek V4 Flash 0731's coding index rests on 4 independent benchmarks and Gemini 3.1 Pro Preview's on 4. Where only one model has a result, the page says so instead of naming a winner.