Gemini 3.1 Flash Lite vs Gemini 3.5 Flash
Updated October 21, 2026. 14 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
vs boards won of 14 shared, 1 tied
Decision reading
Only Gemini 3.5 Flash has a coding score, 39.8 on the Vibe Coding Index; Gemini 3.1 Flash Lite has none, so the two cannot be ranked on coding.
Gemini 3.1 Flash Lite has the edge where output tokens cost 6.0x less, and where the benchmark that matters is IFBench, where it leads.
Model AGemini 3.1 Flash LiteGoogleNot benchmarkedNo coding benchmarkNo cost per solved taskModel BGemini 3.5 FlashGoogle39.8/1004 independent benchmarks$1.21 per solved task
- Shared results
- 14
- Gemini 3.1 Flash Lite only
- 1
- Gemini 3.5 Flash only
- 96
- Like-for-like categories
- 6 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, six public coding benchmarks
No call
Only Gemini 3.5 Flash has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
No call
Only Gemini 3.5 Flash has a AA Intelligence Index result, 33.6.
Directional only
Reasoning
GPQA Diamond
No call
Only Gemini 3.5 Flash has a GPQA Diamond result, 92.7%.
Directional only
Knowledge
MMLU Pro
No call
Only Gemini 3.5 Flash has a MMLU Pro result, 89.5%.
Directional only
Web design
Design Arena: websites
No call
Only Gemini 3.5 Flash has a Design Arena: websites result, 1268.
Directional only
Long documents
Listed context window
No call
Both take 1.05M tokens.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemini 3.1 Flash Lite
Gemini 3.1 Flash Lite $0.0010, Gemini 3.5 Flash $0.0060 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Gemini 3.5 Flash has the number, $1.21.
Directional only
At a glance
- Coding index
- Gemini 3.1 Flash Lite not benchmarked, Gemini 3.5 Flash 39.8 from 4 benchmarks.
- Widest category
- Agentic work, 64.3 points apart on average over 1 shared benchmark.
- Widest single gap
- τ²-Bench Telecom: Gemini 3.1 Flash Lite 31.3% against Gemini 3.5 Flash 95.6%, 64.3 points apart on a 0 to 100 scale.
- Output price
- Gemini 3.1 Flash Lite $1.50 against Gemini 3.5 Flash $9.00 per million output tokens, 6.0x 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 | Gemini 3.1 Flash Lite | Bars | Gemini 3.5 Flash | Ties |
|---|---|---|---|---|
| Coding | 0 | 3 | ||
| Intelligence | 0 | 1 | ||
| Agentic work | 0 | 1 | ||
| Reasoning | 0 | 3 | ||
| Math | 0 | 2 | ||
| General | 1 | 2 | 1 tie | |
| All shared boards | 1 | 12 | 1 tie |
CodingLike-for-likeSix of these boards feed the Vibe Coding Index03
| Benchmark | Gemini 3.1 Flash Lite | Gemini 3.5 Flash | Leader |
|---|---|---|---|
| LMArena WebDev | Not measured | 1499 | Only Gemini 3.5 Flash measured |
| LiveCodeBench (Vals AI) | Not measured | 87.6% | Only Gemini 3.5 Flash measured |
| SWE-bench Verified (Vals AI) | Not measured | 78.8% | Only Gemini 3.5 Flash measured |
| Terminal-Bench 4 (Vals AI) | Not measured | 6.1% | Only Gemini 3.5 Flash measured |
| Vibe Code Bench (Vals AI) | Not measured | 48.7% | Only Gemini 3.5 Flash measured |
| Code migration (Vals AI) | Not measured | 26.8% | Only Gemini 3.5 Flash measured |
| ProgramBench (Vals AI) | Not measured | 0.0% | Only Gemini 3.5 Flash measured |
| Terminal-Bench 2.1 (Vals AI) | Not measured | 74.2% | Only Gemini 3.5 Flash measured |
| SkillsBench (Vals AI) | Not measured | 52.7% | Only Gemini 3.5 Flash measured |
| SciCode | 43.4% | 53.9% | Gemini 3.5 Flash |
| Terminal-Bench Hard (Artificial Analysis run) | 24.2% | 46.2% | Gemini 3.5 Flash |
| WeirdML | 52.2% | 62.6% | Gemini 3.5 Flash |
| ALE-Bench | Not measured | 911.0 | Only Gemini 3.5 Flash measured |
| LMArena Text: coding | Not measured | 1493 | Only Gemini 3.5 Flash measured |
| LMArena Text: software and IT | Not measured | 1494 | Only Gemini 3.5 Flash measured |
| LMArena WebDev: React | Not measured | 1495 | Only Gemini 3.5 Flash measured |
| LMArena WebDev: HTML | Not measured | 1522 | Only Gemini 3.5 Flash measured |
| LMArena WebDev: from an image | Not measured | 1504 | Only Gemini 3.5 Flash 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 | Gemini 3.1 Flash Lite | Gemini 3.5 Flash | Leader |
|---|---|---|---|
| AA Intelligence Index | Not measured | 33.6 | Only Gemini 3.5 Flash measured |
| Epoch Capabilities Index | 144.3 | 154.9 | Gemini 3.5 Flash |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Gemini 3.1 Flash Lite | Gemini 3.5 Flash | Leader |
|---|---|---|---|
| Design Arena: agents building web apps | Not measured | 1202 | Only Gemini 3.5 Flash measured |
| Design Arena: agents building full-stack apps | Not measured | 1197 | Only Gemini 3.5 Flash measured |
| Design Arena: agents building mobile apps | Not measured | 1175 | Only Gemini 3.5 Flash measured |
| Design Arena: agents building Android apps | Not measured | 1190 | Only Gemini 3.5 Flash measured |
| Design Arena: agents building Godot games | Not measured | 1098 | Only Gemini 3.5 Flash measured |
| Design Arena: agents building games | Not measured | 1180 | Only Gemini 3.5 Flash measured |
| Design Arena: HTML slides | Not measured | 1142 | Only Gemini 3.5 Flash measured |
| Design Arena: PowerPoint slides | Not measured | 1179 | Only Gemini 3.5 Flash measured |
| Finance Agent (Vals AI) | Not measured | 57.9% | Only Gemini 3.5 Flash measured |
| Tax Agent Bench (Vals AI) | Not measured | 21.6% | Only Gemini 3.5 Flash measured |
| Legal Research Bench (Vals AI) | Not measured | 30.8% | Only Gemini 3.5 Flash measured |
| Excel Modeling Benchmark (Vals AI) | Not measured | 63.5% | Only Gemini 3.5 Flash measured |
| Terminal-Bench-Science (Vals AI) | Not measured | 5.7% | Only Gemini 3.5 Flash measured |
| τ²-Bench Telecom | 31.3% | 95.6% | Gemini 3.5 Flash |
| APEX-Agents | Not measured | 27.5% | Only Gemini 3.5 Flash measured |
| DeepResearch Bench | 37.3% | Not measured | Only Gemini 3.1 Flash Lite measured |
| Vending-Bench 2 | Not measured | $5,396 | Only Gemini 3.5 Flash measured |
| Neither model has a result on the other 22 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index03
| Benchmark | Gemini 3.1 Flash Lite | Gemini 3.5 Flash | Leader |
|---|---|---|---|
| GPQA Diamond | Not measured | 92.7% | Only Gemini 3.5 Flash measured |
| MMMU Pro (Vals AI) | Not measured | 88.3% | Only Gemini 3.5 Flash measured |
| GPQA Diamond (Artificial Analysis run) | 82.2% | 92.2% | Gemini 3.5 Flash |
| Humanity's Last Exam (Artificial Analysis run) | 17.2% | 42.7% | Gemini 3.5 Flash |
| GPQA Diamond (Epoch AI run) | 81.8% | 92.8% | Gemini 3.5 Flash |
| ARC-AGI | Not measured | 92.5% | Only Gemini 3.5 Flash measured |
| ARC-AGI-2 | Not measured | 72.1% | Only Gemini 3.5 Flash measured |
| SimpleBench | Not measured | 76.7% | Only Gemini 3.5 Flash measured |
| Chess puzzles | Not measured | 45.0% | Only Gemini 3.5 Flash measured |
| Mystery game puzzles | Not measured | 32.0% | Only Gemini 3.5 Flash measured |
| EBR-bench | Not measured | 4.8% | Only Gemini 3.5 Flash measured |
| LMArena Text: hard prompts | Not measured | 1488 | Only Gemini 3.5 Flash measured |
| LMArena Text: expert | Not measured | 1495 | Only Gemini 3.5 Flash measured |
| LMArena Text: hard prompts in English | Not measured | 1483 | Only Gemini 3.5 Flash measured |
| LMArena Vision: diagrams | Not measured | 1323 | Only Gemini 3.5 Flash measured |
| LMArena Vision: homework | Not measured | 1330 | Only Gemini 3.5 Flash measured |
| Neither model has a result on the other 5 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index02
| Benchmark | Gemini 3.1 Flash Lite | Gemini 3.5 Flash | Leader |
|---|---|---|---|
| OTIS Mock AIME | 80.0% | 95.6% | Gemini 3.5 Flash |
| FrontierMath, tiers 1 to 3 | 27.7% | 62.8% | Gemini 3.5 Flash |
| FrontierMath, tier 4 | Not measured | 26.8% | Only Gemini 3.5 Flash measured |
| ProofBench | Not measured | 31.0% | Only Gemini 3.5 Flash measured |
| LMArena Text: math | Not measured | 1504 | Only Gemini 3.5 Flash measured |
| LMArena Text: mathematical work | Not measured | 1495 | Only Gemini 3.5 Flash measured |
| Neither model has a result on the other 7 boards here | |||
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index11 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite | Gemini 3.5 Flash | Leader |
|---|---|---|---|
| MMLU Pro | Not measured | 89.5% | Only Gemini 3.5 Flash measured |
| LegalBench (Vals AI) | Not measured | 83.6% | Only Gemini 3.5 Flash measured |
| CorpFin (Vals AI) | Not measured | 64.7% | Only Gemini 3.5 Flash measured |
| TaxEval (Vals AI) | Not measured | 74.4% | Only Gemini 3.5 Flash measured |
| MortgageTax (Vals AI) | Not measured | 68.1% | Only Gemini 3.5 Flash measured |
| MedCode (Vals AI) | Not measured | 55.8% | Only Gemini 3.5 Flash measured |
| SimpleQA Verified | Not measured | 66.2% | Only Gemini 3.5 Flash measured |
| LMArena Text: science | Not measured | 1495 | Only Gemini 3.5 Flash measured |
| LMArena Text: medicine and healthcare | Not measured | 1483 | Only Gemini 3.5 Flash measured |
| LMArena Text: legal and government | Not measured | 1488 | Only Gemini 3.5 Flash measured |
| LMArena Text: business and finance | Not measured | 1467 | Only Gemini 3.5 Flash measured |
| Neither model has a result on the other 6 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index8 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite | Gemini 3.5 Flash | Leader |
|---|---|---|---|
| Design Arena: websites | Not measured | 1268 | Only Gemini 3.5 Flash measured |
| Design Arena: UI components | Not measured | 1273 | Only Gemini 3.5 Flash measured |
| Design Arena: game dev | Not measured | 1263 | Only Gemini 3.5 Flash measured |
| Design Arena: data viz | Not measured | 1236 | Only Gemini 3.5 Flash measured |
| Design Arena: 3D | Not measured | 1244 | Only Gemini 3.5 Flash measured |
| Design Arena: all code categories | Not measured | 1266 | Only Gemini 3.5 Flash measured |
| Design Arena: SVG | Not measured | 1254 | Only Gemini 3.5 Flash measured |
| Design Arena: ASCII art | Not measured | 1254 | Only Gemini 3.5 Flash measured |
| Neither model has a result on the other 1 board here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index12
| Benchmark | Gemini 3.1 Flash Lite | Gemini 3.5 Flash | Leader |
|---|---|---|---|
| Public Benefits Bench (Vals AI) | Not measured | 59.5% | Only Gemini 3.5 Flash measured |
| SAGE (Vals AI) | Not measured | 49.9% | Only Gemini 3.5 Flash measured |
| MedScribe (Vals AI) | Not measured | 76.6% | Only Gemini 3.5 Flash measured |
| Vals Multimodal Index | Not measured | 62.9% | Only Gemini 3.5 Flash measured |
| IFBench | 77.2% | 76.3% | Gemini 3.1 Flash Lite |
| Long context reasoning (AA-LCR) | 74.3% | 74.3% | Tie |
| DTBench | 76.8% | 94.7% | Gemini 3.5 Flash |
| LMCA | 35.0% | 47.1% | Gemini 3.5 Flash |
| Surface Evolver Bench | Not measured | 58.1% | Only Gemini 3.5 Flash measured |
| LMArena Text | Not measured | 1482 | Only Gemini 3.5 Flash measured |
| LMArena Text: instruction following | Not measured | 1467 | Only Gemini 3.5 Flash measured |
| LMArena Text: creative writing | Not measured | 1470 | Only Gemini 3.5 Flash measured |
| LMArena Vision | Not measured | 1308 | Only Gemini 3.5 Flash measured |
| LMArena Text: English | Not measured | 1481 | Only Gemini 3.5 Flash measured |
| LMArena Text: non-English | Not measured | 1475 | Only Gemini 3.5 Flash measured |
| LMArena Text: Chinese | Not measured | 1527 | Only Gemini 3.5 Flash measured |
| LMArena Text: German | Not measured | 1494 | Only Gemini 3.5 Flash measured |
| LMArena Text: Japanese | Not measured | 1486 | Only Gemini 3.5 Flash measured |
| LMArena Text: Korean | Not measured | 1448 | Only Gemini 3.5 Flash measured |
| LMArena Text: French | Not measured | 1490 | Only Gemini 3.5 Flash measured |
| LMArena Text: Spanish | Not measured | 1480 | Only Gemini 3.5 Flash measured |
| LMArena Text: Russian | Not measured | 1493 | Only Gemini 3.5 Flash measured |
| LMArena Text: Polish | Not measured | 1516 | Only Gemini 3.5 Flash measured |
| LMArena Text: multi-turn | Not measured | 1481 | Only Gemini 3.5 Flash measured |
| LMArena Text: longer queries | Not measured | 1483 | Only Gemini 3.5 Flash measured |
| LMArena Text: writing and language | Not measured | 1478 | Only Gemini 3.5 Flash measured |
| LMArena Text: entertainment and media | Not measured | 1459 | Only Gemini 3.5 Flash measured |
| LMArena Vision: English | Not measured | 1305 | Only Gemini 3.5 Flash measured |
| LMArena Vision: Chinese | Not measured | 1377 | Only Gemini 3.5 Flash measured |
| LMArena Vision: reading text | Not measured | 1317 | Only Gemini 3.5 Flash measured |
| LMArena Vision: humor | Not measured | 1321 | Only Gemini 3.5 Flash measured |
| LMArena Vision: creative writing | Not measured | 1301 | Only Gemini 3.5 Flash measured |
| LMArena Document | Not measured | 1463 | Only Gemini 3.5 Flash measured |
| Neither model has a result on the other 13 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite | Gemini 3.5 Flash | 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
Gemini 3.1 Flash Lite$0.0010Fits in one request
Gemini 3.5 Flash$0.0060Fits in one request
Gemini 3.1 Flash Lite costs less
Repository review
50K input + 3K output tokens
Gemini 3.1 Flash Lite$0.017Fits in one request
Gemini 3.5 Flash$0.102Fits in one request
Gemini 3.1 Flash Lite costs less
Agent loop
200K input + 10K output tokens
Gemini 3.1 Flash Lite$0.065Fits in one request
Gemini 3.5 Flash$0.390Fits in one request
Gemini 3.1 Flash Lite 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 | Google Gemini 3.1 Flash Lite | Google Gemini 3.5 Flash |
|---|---|---|
| Maker | ||
| Weights | No public weights listed | No public weights listed |
| Released | May 7, 2026 | May 19, 2026 |
| Context window | 1.05M | 1.05M |
| Input $/Mtok | $0.25 | $1.50 |
| Output $/Mtok | $1.50 | $9.00 |
| Coding index | Not benchmarked | 39.8 |
| Independent measurements behind it | 0 | 4 |
| Cost per solved task | Not computable | $1.21 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 3.1 Flash Lite better than Gemini 3.5 Flash for coding?
Only Gemini 3.5 Flash has a coding score, 39.8 on the Vibe Coding Index; Gemini 3.1 Flash Lite has none, so the two cannot be ranked on coding. Gemini 3.1 Flash Lite has the edge where output tokens cost 6.0x less, and where the benchmark that matters is IFBench, where it leads.
Which is cheaper, Gemini 3.1 Flash Lite or Gemini 3.5 Flash?
Gemini 3.1 Flash Lite costs $0.25 per million input tokens and $1.50 per million output tokens; Gemini 3.5 Flash costs $1.50 and $9.00. Cost per solved task is known for Gemini 3.5 Flash only.
Which has the bigger context window, Gemini 3.1 Flash Lite or Gemini 3.5 Flash?
Neither: both take 1.05M tokens.
How many benchmarks is the Gemini 3.1 Flash Lite vs Gemini 3.5 Flash comparison based on?
14 benchmarks have a result for both models as of October 21, 2026. Gemini 3.1 Flash Lite's coding index rests on 0 independent benchmarks and Gemini 3.5 Flash's on 4. Where only one model has a result, the page says so instead of naming a winner.