Gemini 3 Flash Preview vs o3 Mini
Updated October 21, 2026. 33 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.
Decision reading
Pick Gemini 3 Flash Preview for coding: it scores 75.8 on the Vibe Coding Index against 52.1 for o3 Mini, though on 1 benchmark against 2.
o3 Mini is neither cheaper nor larger in context, and leads no benchmark both models were measured on.
- Shared results
- 33
- Gemini 3 Flash Preview only
- 36
- o3 Mini only
- 37
- Like-for-like categories
- 7 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
Gemini 3 Flash Preview
Gemini 3 Flash Preview scores 75.8 against 52.1.
1 and 2 benchmarks behind the scores
Intelligence
AA Intelligence Index
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 26.3 against 12.5.
Same board, both measured
Reasoning
GPQA Diamond
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 87.9% against 75.5%.
Same board, both measured
Math
AIME
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 95.6% against 86.5%.
Same board, both measured
Knowledge
MMLU Pro
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 88.6% against 78.7%.
Same board, both measured
Web design
Design Arena: websites
No call
Only Gemini 3 Flash Preview has a Design Arena: websites result, 1196.
Directional only
Long documents
Listed context window
Gemini 3 Flash Preview
Gemini 3 Flash Preview takes 1.05M tokens against 200K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemini 3 Flash Preview
Gemini 3 Flash Preview $0.0020, o3 Mini $0.0033 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only Gemini 3 Flash Preview has the number, $0.37.
Directional only
At a glance
- Coding index
- Gemini 3 Flash Preview 75.8 from 1 benchmark, o3 Mini 52.1 from 2 benchmarks.
- Widest category
- Agentic work, 49.1 points apart on average over 1 shared benchmark.
- Widest single gap
- SimpleQA Verified: Gemini 3 Flash Preview 66.8% against o3 Mini 15.3%, 51.5 points apart on a 0 to 100 scale.
- Output price
- Gemini 3 Flash Preview $3.00 against o3 Mini $4.40 per million output tokens, 1.5x apart.
- Context window
- Gemini 3 Flash Preview takes 1.05M tokens, o3 Mini 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 Flash Preview | Bars | o3 Mini | Ties |
|---|---|---|---|---|
| Coding | 6 | 0 | ||
| Intelligence | 1 | 0 | ||
| Agentic work | 1 | 0 | ||
| Reasoning | 9 | 0 | ||
| Math | 5 | 0 | ||
| Knowledge | 7 | 0 | ||
| General | 4 | 0 | ||
| All shared boards | 33 | 0 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index60
| Benchmark | Gemini 3 Flash Preview | o3 Mini | Leader |
|---|---|---|---|
| Aider polyglot | Not measured | 60.4% | Only o3 Mini measured |
| SWE-bench Verified | 75.8% | 42.4% | Gemini 3 Flash Preview |
| SWE-bench Lite | Not measured | 32.3% | Only o3 Mini measured |
| LiveCodeBench (Vals AI) | 85.6% | 71.5% | Gemini 3 Flash Preview |
| SWE-bench Verified (Vals AI) | 75.0% | Not measured | Only Gemini 3 Flash Preview measured |
| Vibe Code Bench (Vals AI) | 20.2% | Not measured | Only Gemini 3 Flash Preview measured |
| Code migration (Vals AI) | 6.4% | Not measured | Only Gemini 3 Flash Preview measured |
| ProgramBench (Vals AI) | 0.0% | Not measured | Only Gemini 3 Flash Preview measured |
| Terminal-Bench 2.1 (Vals AI) | 53.9% | Not measured | Only Gemini 3 Flash Preview measured |
| LiveCodeBench (Artificial Analysis run) | 90.8% | 73.4% | Gemini 3 Flash Preview |
| SciCode | Not measured | 42.8% | Only o3 Mini measured |
| Terminal-Bench Hard (Artificial Analysis run) | 38.6% | 6.8% | Gemini 3 Flash Preview |
| Terminal-Bench | 64.3% | Not measured | Only Gemini 3 Flash Preview measured |
| GSO-Bench | 9.8% | 1.3% | Gemini 3 Flash Preview |
| WeirdML | 61.6% | 43.7% | Gemini 3 Flash Preview |
| Cybench | Not measured | 22.5% | Only o3 Mini measured |
| ALE-Bench | 1367.2 | Not measured | Only Gemini 3 Flash Preview measured |
| LMArena Text: coding | Not measured | 1378 | Only o3 Mini measured |
| LMArena Text: software and IT | Not measured | 1364 | Only o3 Mini measured |
| Neither model has a result on the other 19 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Gemini 3 Flash Preview | o3 Mini | Leader |
|---|---|---|---|
| AA Intelligence Index | 26.3 | 12.5 | Gemini 3 Flash Preview |
| Epoch Capabilities Index | Not measured | 140.2 | Only o3 Mini measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Gemini 3 Flash Preview | o3 Mini | Leader |
|---|---|---|---|
| Design Arena: agents building web apps | 1111 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: agents building full-stack apps | 1063 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: agents building mobile apps | 1090 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: agents building Android apps | 1056 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: agents building Godot games | 1161 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: PowerPoint slides | 1036 | Not measured | Only Gemini 3 Flash Preview measured |
| Finance Agent (Vals AI) | 42.5% | Not measured | Only Gemini 3 Flash Preview measured |
| Tax Agent Bench (Vals AI) | 11.8% | Not measured | Only Gemini 3 Flash Preview measured |
| Legal Research Bench (Vals AI) | 18.3% | Not measured | Only Gemini 3 Flash Preview measured |
| Excel Modeling Benchmark (Vals AI) | 26.0% | Not measured | Only Gemini 3 Flash Preview measured |
| τ²-Bench Telecom | 80.4% | 31.3% | Gemini 3 Flash Preview |
| BALROG | 48.1% | Not measured | Only Gemini 3 Flash Preview measured |
| DeepResearch Bench | 49.8% | Not measured | Only Gemini 3 Flash Preview measured |
| Vending-Bench 2 | $3,635 | Not measured | Only Gemini 3 Flash Preview measured |
| Neither model has a result on the other 25 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index90
| Benchmark | Gemini 3 Flash Preview | o3 Mini | Leader |
|---|---|---|---|
| GPQA Diamond | 87.9% | 75.5% | Gemini 3 Flash Preview |
| MMMU Pro (Vals AI) | 87.6% | Not measured | Only Gemini 3 Flash Preview measured |
| GPQA Diamond (Artificial Analysis run) | 89.8% | 77.3% | Gemini 3 Flash Preview |
| Humanity's Last Exam (Artificial Analysis run) | 36.6% | 12.0% | Gemini 3 Flash Preview |
| GPQA Diamond (Epoch AI run) | 89.4% | 77.0% | Gemini 3 Flash Preview |
| ARC-AGI | 84.7% | 34.5% | Gemini 3 Flash Preview |
| ARC-AGI-2 | 33.6% | 3.0% | Gemini 3 Flash Preview |
| SimpleBench | 61.1% | 22.8% | Gemini 3 Flash Preview |
| Chess puzzles | 39.0% | 15.0% | Gemini 3 Flash Preview |
| Mystery game puzzles | 26.0% | 7.0% | Gemini 3 Flash Preview |
| VPCT | 72.6% | Not measured | Only Gemini 3 Flash Preview measured |
| LMArena Text: hard prompts | Not measured | 1365 | Only o3 Mini measured |
| LMArena Text: expert | Not measured | 1364 | Only o3 Mini measured |
| LMArena Text: hard prompts in English | Not measured | 1375 | Only o3 Mini measured |
| Neither model has a result on the other 7 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index50
| Benchmark | Gemini 3 Flash Preview | o3 Mini | Leader |
|---|---|---|---|
| AIME | 95.6% | 86.5% | Gemini 3 Flash Preview |
| MATH 500 (Vals AI) | Not measured | 91.8% | Only o3 Mini measured |
| MGSM (Vals AI) | 93.3% | 91.3% | Gemini 3 Flash Preview |
| AA Math Index | 97.0 | Not measured | Only Gemini 3 Flash Preview measured |
| AIME 2025 (Artificial Analysis run) | 97.0% | Not measured | Only Gemini 3 Flash Preview measured |
| OTIS Mock AIME | 95.6% | 76.9% | Gemini 3 Flash Preview |
| FrontierMath, tiers 1 to 3 | 51.2% | 18.6% | Gemini 3 Flash Preview |
| FrontierMath, tier 4 | 17.1% | 0.0% | Gemini 3 Flash Preview |
| ProofBench | 15.0% | Not measured | Only Gemini 3 Flash Preview measured |
| MATH level 5 | Not measured | 96.5% | Only o3 Mini measured |
| LMArena Text: math | Not measured | 1396 | Only o3 Mini measured |
| LMArena Text: mathematical work | Not measured | 1399 | Only o3 Mini measured |
| Neither model has a result on the other 1 board here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index70
| Benchmark | Gemini 3 Flash Preview | o3 Mini | Leader |
|---|---|---|---|
| MMLU Pro | 88.6% | 78.7% | Gemini 3 Flash Preview |
| LegalBench (Vals AI) | 86.9% | 71.5% | Gemini 3 Flash Preview |
| CaseLaw (Vals AI) | 55.8% | Not measured | Only Gemini 3 Flash Preview measured |
| CorpFin (Vals AI) | 66.4% | 45.3% | Gemini 3 Flash Preview |
| TaxEval (Vals AI) | 73.9% | 69.4% | Gemini 3 Flash Preview |
| MortgageTax (Vals AI) | 68.7% | Not measured | Only Gemini 3 Flash Preview measured |
| MedQA (Vals AI) | 95.8% | 94.8% | Gemini 3 Flash Preview |
| MedCode (Vals AI) | 55.9% | Not measured | Only Gemini 3 Flash Preview measured |
| MMLU Pro (Artificial Analysis run) | 89.0% | 80.2% | Gemini 3 Flash Preview |
| SimpleQA Verified | 66.8% | 15.3% | Gemini 3 Flash Preview |
| GeoBench | 88.0% | Not measured | Only Gemini 3 Flash Preview measured |
| LMArena Text: science | Not measured | 1339 | Only o3 Mini measured |
| LMArena Text: medicine and healthcare | Not measured | 1330 | Only o3 Mini measured |
| LMArena Text: legal and government | Not measured | 1328 | Only o3 Mini measured |
| LMArena Text: business and finance | Not measured | 1313 | Only o3 Mini measured |
| Neither model has a result on the other 2 boards here | |||
Web designDirectional onlyPublic boards, shown as published, kept out of the index4 boards, none shared
| Benchmark | Gemini 3 Flash Preview | o3 Mini | Leader |
|---|---|---|---|
| Design Arena: websites | 1196 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: game dev | 1166 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: 3D | 1184 | Not measured | Only Gemini 3 Flash Preview measured |
| Design Arena: all code categories | 1189 | Not measured | Only Gemini 3 Flash Preview measured |
| Neither model has a result on the other 5 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Gemini 3 Flash Preview | o3 Mini | Leader |
|---|---|---|---|
| SAGE (Vals AI) | 51.8% | Not measured | Only Gemini 3 Flash Preview measured |
| MedScribe (Vals AI) | 69.9% | Not measured | Only Gemini 3 Flash Preview measured |
| Vals Multimodal Index | 52.2% | Not measured | Only Gemini 3 Flash Preview measured |
| IFBench | 78.0% | 67.1% | Gemini 3 Flash Preview |
| Long context reasoning (AA-LCR) | 78.0% | 43.0% | Gemini 3 Flash Preview |
| DTBench | 89.1% | 68.8% | Gemini 3 Flash Preview |
| LMCA | 43.1% | 19.0% | Gemini 3 Flash Preview |
| Fiction.LiveBench | Not measured | 50.0% | Only o3 Mini measured |
| Creative writing (Lech Mazur) | Not measured | 61.7% | Only o3 Mini measured |
| LMArena Text | Not measured | 1337 | Only o3 Mini measured |
| LMArena Text: instruction following | Not measured | 1337 | Only o3 Mini measured |
| LMArena Text: creative writing | Not measured | 1286 | Only o3 Mini measured |
| LMArena Text: English | Not measured | 1351 | Only o3 Mini measured |
| LMArena Text: non-English | Not measured | 1319 | Only o3 Mini measured |
| LMArena Text: Chinese | Not measured | 1379 | Only o3 Mini measured |
| LMArena Text: German | Not measured | 1303 | Only o3 Mini measured |
| LMArena Text: Japanese | Not measured | 1286 | Only o3 Mini measured |
| LMArena Text: Korean | Not measured | 1313 | Only o3 Mini measured |
| LMArena Text: French | Not measured | 1334 | Only o3 Mini measured |
| LMArena Text: Spanish | Not measured | 1321 | Only o3 Mini measured |
| LMArena Text: Russian | Not measured | 1304 | Only o3 Mini measured |
| LMArena Text: Polish | Not measured | 1294 | Only o3 Mini measured |
| LMArena Text: multi-turn | Not measured | 1320 | Only o3 Mini measured |
| LMArena Text: longer queries | Not measured | 1343 | Only o3 Mini measured |
| LMArena Text: writing and language | Not measured | 1313 | Only o3 Mini measured |
| LMArena Text: entertainment and media | Not measured | 1283 | Only o3 Mini measured |
| Neither model has a result on the other 20 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3 Flash Preview | o3 Mini | 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 Flash Preview costs less
Repository review
50K input + 3K output tokens
Gemini 3 Flash Preview costs less
Agent loop
200K input + 10K output tokens
Gemini 3 Flash 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 Flash Preview | OpenAI o3 Mini |
|---|---|---|
| Maker | OpenAI | |
| Weights | No public weights listed | No public weights listed |
| Released | December 17, 2025 | January 31, 2025 |
| Context window | 1.05M | 200K |
| Input $/Mtok | $0.50 | $1.10 |
| Output $/Mtok | $3.00 | $4.40 |
| Coding index | 75.8 | 52.1 |
| Independent measurements behind it | 1 | 2 |
| Cost per solved task | $0.37 | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 3 Flash Preview better than o3 Mini for coding?
Pick Gemini 3 Flash Preview for coding: it scores 75.8 on the Vibe Coding Index against 52.1 for o3 Mini, though on 1 benchmark against 2. o3 Mini is neither cheaper nor larger in context, and leads no benchmark both models were measured on.
Which is cheaper, Gemini 3 Flash Preview or o3 Mini?
Gemini 3 Flash Preview costs $0.50 per million input tokens and $3.00 per million output tokens; o3 Mini costs $1.10 and $4.40. Cost per solved task is known for Gemini 3 Flash Preview only.
Which has the bigger context window, Gemini 3 Flash Preview or o3 Mini?
Gemini 3 Flash Preview, with 1.05M tokens against 200K.
How many benchmarks is the Gemini 3 Flash Preview vs o3 Mini comparison based on?
33 benchmarks have a result for both models as of October 21, 2026. Gemini 3 Flash Preview's coding index rests on 1 independent benchmark and o3 Mini's on 2. Where only one model has a result, the page says so instead of naming a winner.