DeepSeek V3.1 Terminus vs Gemini 3.5 Flash Lite
Gemini 3.5 Flash Lite leads DeepSeek V3.1 Terminus on the Artificial Analysis Intelligence Index, 22.2 to 14.8, and DeepSeek V3.1 Terminus costs 2.5x less per output token ($1.0142 vs $2.50 per million). Updated October 21, 2026; 30 benchmarks have a result for both.
DeepSeek V3.1 Terminus or Gemini 3.5 Flash Lite: which to pick
Only Gemini 3.5 Flash Lite has a coding score, 49.0 on the Vibe Coding Index; DeepSeek V3.1 Terminus has none, so the two cannot be ranked on coding.
Pick DeepSeek V3.1 Terminus for output tokens 2.5x cheaper ($1.0142 vs $2.50 per million) and work measured by LMArena Text: science or LMArena Text: medicine and healthcare, where it leads.
- Shared results
- 30
- DeepSeek V3.1 Terminus only
- 15
- Gemini 3.5 Flash Lite only
- 55
- 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 Gemini 3.5 Flash Lite has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
Gemini 3.5 Flash Lite
Gemini 3.5 Flash Lite leads, 22.2 against 14.8.
Same board, both measured
Agentic work
AA Agentic Index
Gemini 3.5 Flash Lite
Gemini 3.5 Flash Lite leads, 14.3 against 6.8.
Same board, both measured
Reasoning
GPQA Diamond
No call
Only Gemini 3.5 Flash Lite has a GPQA Diamond result, 83.8%.
Directional only
Knowledge
MMLU Pro
No call
Only Gemini 3.5 Flash Lite has a MMLU Pro result, 85.8%.
Directional only
Web design
Design Arena: websites
No call
Only DeepSeek V3.1 Terminus has a Design Arena: websites result, 1187.
Directional only
Long documents
Listed context window
Gemini 3.5 Flash Lite
Gemini 3.5 Flash Lite takes 1.05M tokens against 164K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
DeepSeek V3.1 Terminus
DeepSeek V3.1 Terminus $0.0008, Gemini 3.5 Flash Lite $0.0015 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Gemini 3.5 Flash Lite has the number, $0.41.
Directional only
At a glance
- Coding index
- DeepSeek V3.1 Terminus not benchmarked, Gemini 3.5 Flash Lite 49.0 from 3 benchmarks.
- Widest category
- Agentic work, 7.5 points apart on average over 1 shared benchmark.
- Widest single gap
- LMCA: DeepSeek V3.1 Terminus 28.6% against Gemini 3.5 Flash Lite 37.6%, 9.0 points apart on a 0 to 100 scale.
- Output price
- DeepSeek V3.1 Terminus $1.0142 against Gemini 3.5 Flash Lite $2.50 per million output tokens, 2.5x apart.
- Context window
- DeepSeek V3.1 Terminus takes 164K tokens, Gemini 3.5 Flash Lite 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 V3.1 Terminus | Bars | Gemini 3.5 Flash Lite | Ties |
|---|---|---|---|---|
| Coding | 0 | 5 | ||
| Intelligence | 0 | 1 | ||
| Agentic work | 0 | 1 | ||
| Reasoning | 0 | 4 | ||
| Math | 0 | 1 | ||
| Knowledge | 3 | 1 | ||
| General | 0 | 14 | ||
| All shared boards | 3 | 27 |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index05
| Benchmark | DeepSeek V3.1 Terminus | Gemini 3.5 Flash Lite | Leader |
|---|---|---|---|
| LMArena WebDev | Not measured | 1435 | Only Gemini 3.5 Flash Lite measured |
| AA Coding Index | 43.5 | 49.3 | Gemini 3.5 Flash Lite |
| LiveCodeBench (Vals AI) | Not measured | 79.0% | Only Gemini 3.5 Flash Lite measured |
| SWE-bench Verified (Vals AI) | Not measured | 75.0% | Only Gemini 3.5 Flash Lite measured |
| Vibe Code Bench (Vals AI) | Not measured | 37.2% | Only Gemini 3.5 Flash Lite measured |
| Code migration (Vals AI) | Not measured | 6.2% | Only Gemini 3.5 Flash Lite measured |
| ProgramBench (Vals AI) | Not measured | 0.0% | Only Gemini 3.5 Flash Lite measured |
| Terminal-Bench 2.1 (Vals AI) | Not measured | 50.2% | Only Gemini 3.5 Flash Lite measured |
| CyberBench (Vals AI) | Not measured | 59.1% | Only Gemini 3.5 Flash Lite measured |
| LiveCodeBench (Artificial Analysis run) | 79.8% | Not measured | Only DeepSeek V3.1 Terminus measured |
| SciCode | 38.0% | 41.3% | Gemini 3.5 Flash Lite |
| Terminal-Bench Hard (Artificial Analysis run) | 31.8% | Not measured | Only DeepSeek V3.1 Terminus measured |
| WeirdML | Not measured | 39.0% | Only Gemini 3.5 Flash Lite measured |
| ALE-Bench | 745.2 | 765.3 | Gemini 3.5 Flash Lite |
| LMArena Text: coding | 1425 | 1453 | Gemini 3.5 Flash Lite |
| LMArena Text: software and IT | 1426 | 1451 | Gemini 3.5 Flash Lite |
| LMArena WebDev: React | Not measured | 1408 | Only Gemini 3.5 Flash Lite measured |
| LMArena WebDev: from an image | Not measured | 1448 | Only Gemini 3.5 Flash Lite measured |
| SciCode | Not measured | 6.2% | Only Gemini 3.5 Flash Lite measured |
| Neither model has a result on the other 20 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | DeepSeek V3.1 Terminus | Gemini 3.5 Flash Lite | Leader |
|---|---|---|---|
| AA Intelligence Index | 14.8 | 22.2 | Gemini 3.5 Flash Lite |
| Epoch Capabilities Index | Not measured | 144.9 | Only Gemini 3.5 Flash Lite measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | DeepSeek V3.1 Terminus | Gemini 3.5 Flash Lite | Leader |
|---|---|---|---|
| AA Agentic Index | 6.8 | 14.3 | Gemini 3.5 Flash Lite |
| Finance Agent (Vals AI) | Not measured | 47.4% | Only Gemini 3.5 Flash Lite measured |
| Tax Agent Bench (Vals AI) | Not measured | 7.2% | Only Gemini 3.5 Flash Lite measured |
| Legal Research Bench (Vals AI) | Not measured | 13.9% | Only Gemini 3.5 Flash Lite measured |
| Excel Modeling Benchmark (Vals AI) | Not measured | 43.2% | Only Gemini 3.5 Flash Lite measured |
| τ²-Bench Telecom | 37.1% | Not measured | Only DeepSeek V3.1 Terminus measured |
| APEX-Agents | Not measured | 29.3% | Only Gemini 3.5 Flash Lite measured |
| Neither model has a result on the other 34 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index04
| Benchmark | DeepSeek V3.1 Terminus | Gemini 3.5 Flash Lite | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 83.8% | Only Gemini 3.5 Flash Lite measured |
| MMMU Pro (Vals AI) | Not measured | 83.6% | Only Gemini 3.5 Flash Lite measured |
| GPQA Diamond (Artificial Analysis run) | 79.2% | 83.8% | Gemini 3.5 Flash Lite |
| Humanity's Last Exam (Artificial Analysis run) | 16.4% | 18.8% | Gemini 3.5 Flash Lite |
| GPQA Diamond (Epoch AI run) | Not measured | 83.3% | Only Gemini 3.5 Flash Lite measured |
| ARC-AGI | Not measured | 53.5% | Only Gemini 3.5 Flash Lite measured |
| ARC-AGI-2 | Not measured | 10.3% | Only Gemini 3.5 Flash Lite measured |
| Chess puzzles | Not measured | 21.0% | Only Gemini 3.5 Flash Lite measured |
| Mystery game puzzles | Not measured | 19.0% | Only Gemini 3.5 Flash Lite measured |
| LMArena Text: hard prompts | 1426 | 1441 | Gemini 3.5 Flash Lite |
| LMArena Text: expert | Not measured | 1434 | Only Gemini 3.5 Flash Lite measured |
| LMArena Text: hard prompts in English | 1432 | 1440 | Gemini 3.5 Flash Lite |
| LMArena Vision: diagrams | Not measured | 1284 | Only Gemini 3.5 Flash Lite measured |
| LMArena Vision: homework | Not measured | 1291 | Only Gemini 3.5 Flash Lite measured |
| Kagi LLM Benchmark | 57.4% | Not measured | Only DeepSeek V3.1 Terminus measured |
| Neither model has a result on the other 7 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | DeepSeek V3.1 Terminus | Gemini 3.5 Flash Lite | Leader |
|---|---|---|---|
| AA Math Index | 89.7 | Not measured | Only DeepSeek V3.1 Terminus measured |
| AIME 2025 (Artificial Analysis run) | 89.7% | Not measured | Only DeepSeek V3.1 Terminus measured |
| OTIS Mock AIME | Not measured | 71.1% | Only Gemini 3.5 Flash Lite measured |
| FrontierMath, tiers 1 to 3 | Not measured | 26.0% | Only Gemini 3.5 Flash Lite measured |
| FrontierMath, tier 4 | Not measured | 0.0% | Only Gemini 3.5 Flash Lite measured |
| ProofBench | Not measured | 13.0% | Only Gemini 3.5 Flash Lite measured |
| LMArena Text: math | 1402 | 1434 | Gemini 3.5 Flash Lite |
| LMArena Text: mathematical work | Not measured | 1433 | Only Gemini 3.5 Flash Lite measured |
| Neither model has a result on the other 5 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index31
| Benchmark | DeepSeek V3.1 Terminus | Gemini 3.5 Flash Lite | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 85.8% | Only Gemini 3.5 Flash Lite measured |
| LegalBench (Vals AI) | Not measured | 84.1% | Only Gemini 3.5 Flash Lite measured |
| CorpFin (Vals AI) | Not measured | 60.7% | Only Gemini 3.5 Flash Lite measured |
| TaxEval (Vals AI) | Not measured | 72.6% | Only Gemini 3.5 Flash Lite measured |
| MortgageTax (Vals AI) | Not measured | 68.7% | Only Gemini 3.5 Flash Lite measured |
| MedCode (Vals AI) | Not measured | 43.5% | Only Gemini 3.5 Flash Lite measured |
| MMLU Pro (Artificial Analysis run) | 85.1% | Not measured | Only DeepSeek V3.1 Terminus measured |
| LMArena Text: science | 1451 | 1451 | DeepSeek V3.1 Terminus |
| LMArena Text: medicine and healthcare | 1468 | 1438 | DeepSeek V3.1 Terminus |
| LMArena Text: legal and government | 1457 | 1431 | DeepSeek V3.1 Terminus |
| LMArena Text: business and finance | 1414 | 1423 | Gemini 3.5 Flash Lite |
| FACTS Benchmark Suite | Not measured | 53.5% | Only Gemini 3.5 Flash Lite measured |
| Neither model has a result on the other 6 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index7 boards, none shared
| Benchmark | DeepSeek V3.1 Terminus | Gemini 3.5 Flash Lite | Leader |
|---|---|---|---|
| Design Arena: websites | 1187 | Not measured | Only DeepSeek V3.1 Terminus measured |
| Design Arena: UI components | 1182 | Not measured | Only DeepSeek V3.1 Terminus measured |
| Design Arena: game dev | 1131 | Not measured | Only DeepSeek V3.1 Terminus measured |
| Design Arena: data viz | 1167 | Not measured | Only DeepSeek V3.1 Terminus measured |
| Design Arena: 3D | 1141 | Not measured | Only DeepSeek V3.1 Terminus measured |
| Design Arena: all code categories | 1175 | Not measured | Only DeepSeek V3.1 Terminus measured |
| Design Arena: SVG | 1065 | Not measured | Only DeepSeek V3.1 Terminus measured |
| Neither model has a result on the other 2 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index014
| Benchmark | DeepSeek V3.1 Terminus | Gemini 3.5 Flash Lite | Leader |
|---|---|---|---|
| Public Benefits Bench (Vals AI) | Not measured | 51.8% | Only Gemini 3.5 Flash Lite measured |
| SAGE (Vals AI) | Not measured | 47.3% | Only Gemini 3.5 Flash Lite measured |
| MedScribe (Vals AI) | Not measured | 70.9% | Only Gemini 3.5 Flash Lite measured |
| IFBench | 57.0% | Not measured | Only DeepSeek V3.1 Terminus measured |
| Long context reasoning (AA-LCR) | 69.3% | 76.0% | Gemini 3.5 Flash Lite |
| DTBench | 81.3% | 83.5% | Gemini 3.5 Flash Lite |
| LMCA | 28.6% | 37.6% | Gemini 3.5 Flash Lite |
| LMArena Text | 1419 | 1435 | Gemini 3.5 Flash Lite |
| LMArena Text: instruction following | 1404 | 1419 | Gemini 3.5 Flash Lite |
| LMArena Text: creative writing | 1403 | 1421 | Gemini 3.5 Flash Lite |
| LMArena Vision | Not measured | 1269 | Only Gemini 3.5 Flash Lite measured |
| LMArena Text: English | 1429 | 1438 | Gemini 3.5 Flash Lite |
| LMArena Text: non-English | 1408 | 1427 | Gemini 3.5 Flash Lite |
| LMArena Text: Chinese | Not measured | 1468 | Only Gemini 3.5 Flash Lite measured |
| LMArena Text: German | Not measured | 1454 | Only Gemini 3.5 Flash Lite measured |
| LMArena Text: Japanese | Not measured | 1426 | Only Gemini 3.5 Flash Lite measured |
| LMArena Text: Korean | Not measured | 1407 | Only Gemini 3.5 Flash Lite measured |
| LMArena Text: French | Not measured | 1451 | Only Gemini 3.5 Flash Lite measured |
| LMArena Text: Spanish | Not measured | 1441 | Only Gemini 3.5 Flash Lite measured |
| LMArena Text: Russian | 1435 | 1443 | Gemini 3.5 Flash Lite |
| LMArena Text: Polish | 1427 | 1437 | Gemini 3.5 Flash Lite |
| LMArena Text: multi-turn | 1411 | 1445 | Gemini 3.5 Flash Lite |
| LMArena Text: longer queries | 1422 | 1435 | Gemini 3.5 Flash Lite |
| LMArena Text: writing and language | 1409 | 1428 | Gemini 3.5 Flash Lite |
| LMArena Text: entertainment and media | 1391 | 1414 | Gemini 3.5 Flash Lite |
| LMArena Vision: English | Not measured | 1269 | Only Gemini 3.5 Flash Lite measured |
| LMArena Vision: Chinese | Not measured | 1311 | Only Gemini 3.5 Flash Lite measured |
| LMArena Vision: reading text | Not measured | 1280 | Only Gemini 3.5 Flash Lite measured |
| LMArena Vision: humor | Not measured | 1287 | Only Gemini 3.5 Flash Lite measured |
| LMArena Vision: creative writing | Not measured | 1260 | Only Gemini 3.5 Flash Lite measured |
| Neither model has a result on the other 16 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | DeepSeek V3.1 Terminus | Gemini 3.5 Flash Lite | 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 V3.1 Terminus costs less
Repository review
50K input + 3K output tokens
DeepSeek V3.1 Terminus costs less
Agent loop
200K input + 10K output tokens
DeepSeek V3.1 Terminus 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 V3.1 Terminus | Google Gemini 3.5 Flash Lite |
|---|---|---|
| Maker | DeepSeek | |
| Weights | Open weights | No public weights listed |
| Released | September 22, 2025 | July 21, 2026 |
| Context window | 164K | 1.05M |
| Input $/Mtok | $0.3063 | $0.30 |
| Output $/Mtok | $1.0142 | $2.50 |
| Coding index | Not benchmarked | 49.0 |
| Independent measurements behind it | 0 | 3 |
| Cost per solved task | Not computable | $0.41 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is DeepSeek V3.1 Terminus better than Gemini 3.5 Flash Lite for coding?
Only Gemini 3.5 Flash Lite has a coding score, 49.0 on the Vibe Coding Index; DeepSeek V3.1 Terminus has none, so the two cannot be ranked on coding. Pick DeepSeek V3.1 Terminus for output tokens 2.5x cheaper ($1.0142 vs $2.50 per million) and work measured by LMArena Text: science or LMArena Text: medicine and healthcare, where it leads.
Which is cheaper, DeepSeek V3.1 Terminus or Gemini 3.5 Flash Lite?
DeepSeek V3.1 Terminus costs $0.3063 per million input tokens and $1.0142 per million output tokens; Gemini 3.5 Flash Lite costs $0.30 and $2.50. Cost per solved task is known for Gemini 3.5 Flash Lite only.
Which has the bigger context window, DeepSeek V3.1 Terminus or Gemini 3.5 Flash Lite?
Gemini 3.5 Flash Lite, with 1.05M tokens against 164K.
How many benchmarks is the DeepSeek V3.1 Terminus vs Gemini 3.5 Flash Lite comparison based on?
30 benchmarks have a result for both models as of October 21, 2026. DeepSeek V3.1 Terminus's coding index rests on 0 independent benchmarks and Gemini 3.5 Flash Lite's on 3. Where only one model has a result, the page says so instead of naming a winner.