Gemini 3.1 Flash Lite Preview vs o3 Pro
Updated October 21, 2026. 1 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
Decision reading
Gemini 3.1 Flash Lite Preview scores 8.1 and o3 Pro 84.9 on the Vibe Coding Index, but no coding benchmark measured both, so the gap is directional, not a ranking.
Pick Gemini 3.1 Flash Lite Preview when output tokens cost 53.3x less, or when the context window is larger, 1.05M against 200K tokens; pick o3 Pro when the benchmark that matters is AA Intelligence Index, where it leads.
- Shared results
- 1
- Gemini 3.1 Flash Lite Preview only
- 76
- o3 Pro only
- 10
- 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
8.1 against 84.9, from different benchmarks with none in common.
Directional only
Intelligence
AA Intelligence Index
o3 Pro
o3 Pro leads, 21.9 against 15.6.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only Gemini 3.1 Flash Lite Preview has a AA Agentic Index result, 1.6.
Directional only
Reasoning
GPQA Diamond
No call
Only Gemini 3.1 Flash Lite Preview has a GPQA Diamond result, 81.1%.
Directional only
Math
AIME
No call
Only Gemini 3.1 Flash Lite Preview has a AIME result, 83.3%.
Directional only
Knowledge
MMLU Pro
No call
Only Gemini 3.1 Flash Lite Preview has a MMLU Pro result, 86.2%.
Directional only
Web design
Design Arena: websites
No call
Only Gemini 3.1 Flash Lite Preview has a Design Arena: websites result, 1083.
Directional only
Long documents
Listed context window
Gemini 3.1 Flash Lite Preview
Gemini 3.1 Flash Lite Preview takes 1.05M tokens against 200K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemini 3.1 Flash Lite Preview
Gemini 3.1 Flash Lite Preview $0.0010, o3 Pro $0.060 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Gemini 3.1 Flash Lite Preview has the number, $0.18.
Directional only
At a glance
- Coding index
- Gemini 3.1 Flash Lite Preview 8.1 from 1 benchmark, o3 Pro 84.9 from 1 benchmark.
- Widest category
- Intelligence, 6.3 points apart on average over 1 shared benchmark.
- Widest single gap
- AA Intelligence Index: Gemini 3.1 Flash Lite Preview 15.6 against o3 Pro 21.9, 6.3 points apart on a 0 to 100 scale.
- Output price
- Gemini 3.1 Flash Lite Preview $1.50 against o3 Pro $80.00 per million output tokens, 53.3x apart.
- Context window
- Gemini 3.1 Flash Lite Preview takes 1.05M tokens, o3 Pro 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 | Gemini 3.1 Flash Lite Preview | Bars | o3 Pro | Ties |
|---|---|---|---|---|
| Intelligence | 0 | 1 | ||
| All shared boards | 0 | 1 |
CodingDirectional onlyFour of these boards feed the Vibe Coding Index16 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite Preview | o3 Pro | Leader |
|---|---|---|---|
| Aider polyglot | Not measured | 84.9% | Only o3 Pro measured |
| LMArena WebDev | 1257 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| AA Coding Index | 34.7 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LiveCodeBench (Vals AI) | 80.1% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| SWE-bench Verified (Vals AI) | 62.8% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Vibe Code Bench (Vals AI) | 0.0% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Code migration (Vals AI) | 4.6% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| ProgramBench (Vals AI) | 0.0% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Terminal-Bench 2.1 (Vals AI) | 34.1% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| WeirdML | Not measured | 58.2% | Only o3 Pro measured |
| ALE-Bench | 797.7 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: coding | 1400 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: software and IT | 1413 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena WebDev: React | 1245 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena WebDev: HTML | 1276 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena WebDev: from an image | 1336 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Neither model has a result on the other 22 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Gemini 3.1 Flash Lite Preview | o3 Pro | Leader |
|---|---|---|---|
| AA Intelligence Index | 15.6 | 21.9 | o3 Pro |
| Epoch Capabilities Index | Not measured | 147.3 | Only o3 Pro measured |
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index5 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite Preview | o3 Pro | Leader |
|---|---|---|---|
| AA Agentic Index | 1.6 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Finance Agent (Vals AI) | 30.0% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Tax Agent Bench (Vals AI) | 3.1% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Legal Research Bench (Vals AI) | 3.4% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Excel Modeling Benchmark (Vals AI) | 8.6% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Neither model has a result on the other 34 boards here | |||
ReasoningDirectional onlyPublic boards, shown as published, kept out of the index10 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite Preview | o3 Pro | Leader |
|---|---|---|---|
| GPQA Diamond | 81.1% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| MMMU Pro (Vals AI) | 82.5% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| GPQA Diamond (Artificial Analysis run) | Not measured | 84.5% | Only o3 Pro measured |
| ARC-AGI | Not measured | 59.3% | Only o3 Pro measured |
| ARC-AGI-2 | Not measured | 4.9% | Only o3 Pro measured |
| LMArena Text: hard prompts | 1407 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: expert | 1398 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: hard prompts in English | 1403 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: diagrams | 1242 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: homework | 1271 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Neither model has a result on the other 11 boards here | |||
MathDirectional onlyPublic boards, shown as published, kept out of the index3 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite Preview | o3 Pro | Leader |
|---|---|---|---|
| AIME | 83.3% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: math | 1428 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: mathematical work | 1417 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Neither model has a result on the other 10 boards here | |||
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index11 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite Preview | o3 Pro | Leader |
|---|---|---|---|
| MMLU Pro | 86.2% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LegalBench (Vals AI) | 83.8% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| CaseLaw (Vals AI) | 55.0% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| CorpFin (Vals AI) | 59.4% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| TaxEval (Vals AI) | 71.8% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| MortgageTax (Vals AI) | 68.0% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| MedCode (Vals AI) | 47.6% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: science | 1425 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: medicine and healthcare | 1428 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: legal and government | 1418 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: business and finance | 1389 | Not measured | Only Gemini 3.1 Flash Lite Preview 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 Preview | o3 Pro | Leader |
|---|---|---|---|
| Design Arena: websites | 1083 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Design Arena: UI components | 1071 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Design Arena: game dev | 1029 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Design Arena: data viz | 1045 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Design Arena: 3D | 1048 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Design Arena: all code categories | 1072 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Design Arena: SVG | 1052 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Design Arena: ASCII art | 1166 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Neither model has a result on the other 1 board here | |||
GeneralDirectional onlyPublic boards, shown as published, kept out of the index32 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite Preview | o3 Pro | Leader |
|---|---|---|---|
| SAGE (Vals AI) | 49.5% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| MedScribe (Vals AI) | 63.9% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Vals Multimodal Index | 41.4% | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| DTBench | Not measured | 86.9% | Only o3 Pro measured |
| LMCA | Not measured | 38.5% | Only o3 Pro measured |
| Fiction.LiveBench | Not measured | 97.2% | Only o3 Pro measured |
| Creative writing (Lech Mazur) | Not measured | 84.4% | Only o3 Pro measured |
| LMArena Text | 1416 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: instruction following | 1377 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: creative writing | 1401 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision | 1240 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: English | 1414 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: non-English | 1410 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: Chinese | 1460 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: German | 1430 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: Japanese | 1413 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: Korean | 1392 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: French | 1424 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: Spanish | 1421 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: Russian | 1420 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: Polish | 1443 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: multi-turn | 1417 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: longer queries | 1394 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: writing and language | 1408 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Text: entertainment and media | 1386 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: English | 1232 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: Chinese | 1278 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: reading text | 1246 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: humor | 1266 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: captioning | 1259 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: recognizing things | 1308 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| LMArena Vision: creative writing | 1248 | Not measured | Only Gemini 3.1 Flash Lite Preview measured |
| Neither model has a result on the other 14 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3.1 Flash Lite Preview | o3 Pro | 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 Preview costs less
Repository review
50K input + 3K output tokens
Gemini 3.1 Flash Lite Preview costs less
Agent loop
200K input + 10K output tokens
Gemini 3.1 Flash Lite Preview 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 Preview | OpenAI o3 Pro |
|---|---|---|
| Maker | OpenAI | |
| Weights | No public weights listed | No public weights listed |
| Released | March 3, 2026 | June 10, 2025 |
| Context window | 1.05M | 200K |
| Input $/Mtok | $0.25 | $20.00 |
| Output $/Mtok | $1.50 | $80.00 |
| Coding index | 8.1 | 84.9 |
| Independent measurements behind it | 1 | 1 |
| Cost per solved task | $0.18 | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 3.1 Flash Lite Preview better than o3 Pro for coding?
Gemini 3.1 Flash Lite Preview scores 8.1 and o3 Pro 84.9 on the Vibe Coding Index, but no coding benchmark measured both, so the gap is directional, not a ranking. Pick Gemini 3.1 Flash Lite Preview when output tokens cost 53.3x less, or when the context window is larger, 1.05M against 200K tokens; pick o3 Pro when the benchmark that matters is AA Intelligence Index, where it leads.
Which is cheaper, Gemini 3.1 Flash Lite Preview or o3 Pro?
Gemini 3.1 Flash Lite Preview costs $0.25 per million input tokens and $1.50 per million output tokens; o3 Pro costs $20.00 and $80.00. Cost per solved task is known for Gemini 3.1 Flash Lite Preview only.
Which has the bigger context window, Gemini 3.1 Flash Lite Preview or o3 Pro?
Gemini 3.1 Flash Lite Preview, with 1.05M tokens against 200K.
How many benchmarks is the Gemini 3.1 Flash Lite Preview vs o3 Pro comparison based on?
1 benchmarks have a result for both models as of October 21, 2026. Gemini 3.1 Flash Lite Preview's coding index rests on 1 independent benchmark and o3 Pro's on 1. Where only one model has a result, the page says so instead of naming a winner.