Gemini 3 Flash Preview vs gpt-oss-120b
Updated October 21, 2026. 37 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 34.5 for gpt-oss-120b, though on 1 benchmark against 2.
Pick gpt-oss-120b when output tokens cost 5.0x less.
- Shared results
- 37
- Gemini 3 Flash Preview only
- 32
- gpt-oss-120b only
- 41
- Like-for-like categories
- 8 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 34.5.
1 and 2 benchmarks behind the scores
Intelligence
AA Intelligence Index
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 26.3 against 11.6.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only gpt-oss-120b has a AA Agentic Index result, 3.7.
Directional only
Reasoning
GPQA Diamond
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 87.9% against 78.5%.
Same board, both measured
Math
AIME
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 95.6% against 92.6%.
Same board, both measured
Knowledge
MMLU Pro
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 88.6% against 79.2%.
Same board, both measured
Web design
Design Arena: websites
Gemini 3 Flash Preview
Gemini 3 Flash Preview leads, 1196 against 968.
Same board, both measured
Long documents
Listed context window
Gemini 3 Flash Preview
Gemini 3 Flash Preview takes 1.05M tokens against 131K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
gpt-oss-120b
Gemini 3 Flash Preview $0.0020, gpt-oss-120b $0.0004 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
Gemini 3 Flash Preview
Gemini 3 Flash Preview $0.37, gpt-oss-120b $0.51.
Published attempt cost and pass rate
At a glance
- Coding index
- Gemini 3 Flash Preview 75.8 from 1 benchmark, gpt-oss-120b 34.5 from 2 benchmarks.
- Widest category
- Web design, 28.5 points apart on average over 4 shared benchmarks.
- Widest single gap
- SWE-bench Verified: Gemini 3 Flash Preview 75.8% against gpt-oss-120b 26.0%, 49.8 points apart on a 0 to 100 scale.
- Output price
- Gemini 3 Flash Preview $3.00 against gpt-oss-120b $0.60 per million output tokens, 5.0x apart.
- Context window
- Gemini 3 Flash Preview takes 1.05M tokens, gpt-oss-120b 131K.
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 | gpt-oss-120b | Ties |
|---|---|---|---|---|
| Coding | 8 | 0 | ||
| Intelligence | 1 | 0 | ||
| Agentic work | 2 | 0 | ||
| Reasoning | 6 | 0 | ||
| Math | 5 | 0 | ||
| Knowledge | 7 | 0 | ||
| Web design | 4 | 0 | ||
| General | 4 | 0 | ||
| All shared boards | 37 | 0 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index80
| Benchmark | Gemini 3 Flash Preview | gpt-oss-120b | Leader |
|---|---|---|---|
| Aider polyglot | Not measured | 41.8% | Only gpt-oss-120b measured |
| SWE-bench Verified | 75.8% | 26.0% | Gemini 3 Flash Preview |
| AA Coding Index | Not measured | 30.4 | Only gpt-oss-120b measured |
| LiveCodeBench (Vals AI) | 85.6% | 83.2% | Gemini 3 Flash Preview |
| SWE-bench Verified (Vals AI) | 75.0% | 33.6% | Gemini 3 Flash Preview |
| 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% | 87.8% | Gemini 3 Flash Preview |
| SciCode | Not measured | 34.0% | Only gpt-oss-120b measured |
| Terminal-Bench Hard (Artificial Analysis run) | 38.6% | 23.5% | Gemini 3 Flash Preview |
| Terminal-Bench | 64.3% | 18.7% | Gemini 3 Flash Preview |
| GSO-Bench | 9.8% | Not measured | Only Gemini 3 Flash Preview measured |
| WeirdML | 61.6% | 48.2% | Gemini 3 Flash Preview |
| ALE-Bench | 1367.2 | 575.6 | Gemini 3 Flash Preview |
| LMArena Text: coding | Not measured | 1379 | Only gpt-oss-120b measured |
| LMArena Text: software and IT | Not measured | 1387 | Only gpt-oss-120b measured |
| Neither model has a result on the other 20 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | Gemini 3 Flash Preview | gpt-oss-120b | Leader |
|---|---|---|---|
| AA Intelligence Index | 26.3 | 11.6 | Gemini 3 Flash Preview |
| Epoch Capabilities Index | Not measured | 139.8 | Only gpt-oss-120b measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index20
| Benchmark | Gemini 3 Flash Preview | gpt-oss-120b | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 3.7 | Only gpt-oss-120b measured |
| 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% | 65.8% | Gemini 3 Flash Preview |
| APEX-Agents | Not measured | 4.4% | Only gpt-oss-120b measured |
| METR time horizons | Not measured | 56.6% | Only gpt-oss-120b measured |
| 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 | -$22 | Gemini 3 Flash Preview |
| Neither model has a result on the other 22 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index60
| Benchmark | Gemini 3 Flash Preview | gpt-oss-120b | Leader |
|---|---|---|---|
| GPQA Diamond | 87.9% | 78.5% | 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% | 78.2% | Gemini 3 Flash Preview |
| Humanity's Last Exam (Artificial Analysis run) | 36.6% | 19.6% | Gemini 3 Flash Preview |
| GPQA Diamond (Epoch AI run) | 89.4% | 75.8% | Gemini 3 Flash Preview |
| ARC-AGI | 84.7% | Not measured | Only Gemini 3 Flash Preview measured |
| ARC-AGI-2 | 33.6% | Not measured | Only Gemini 3 Flash Preview measured |
| SimpleBench | 61.1% | 22.1% | Gemini 3 Flash Preview |
| Chess puzzles | 39.0% | Not measured | Only Gemini 3 Flash Preview measured |
| Mystery game puzzles | 26.0% | 2.0% | Gemini 3 Flash Preview |
| VPCT | 72.6% | Not measured | Only Gemini 3 Flash Preview measured |
| LMArena Text: hard prompts | Not measured | 1364 | Only gpt-oss-120b measured |
| LMArena Text: expert | Not measured | 1356 | Only gpt-oss-120b measured |
| LMArena Text: hard prompts in English | Not measured | 1368 | Only gpt-oss-120b 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 | gpt-oss-120b | Leader |
|---|---|---|---|
| AIME | 95.6% | 92.6% | Gemini 3 Flash Preview |
| MATH 500 (Vals AI) | Not measured | 94.8% | Only gpt-oss-120b measured |
| MGSM (Vals AI) | 93.3% | 92.0% | Gemini 3 Flash Preview |
| AA Math Index | 97.0 | 93.4 | Gemini 3 Flash Preview |
| AIME 2025 (Artificial Analysis run) | 97.0% | 93.4% | Gemini 3 Flash Preview |
| OTIS Mock AIME | 95.6% | 88.9% | Gemini 3 Flash Preview |
| FrontierMath, tiers 1 to 3 | 51.2% | Not measured | Only Gemini 3 Flash Preview measured |
| FrontierMath, tier 4 | 17.1% | Not measured | Only Gemini 3 Flash Preview measured |
| ProofBench | 15.0% | Not measured | Only Gemini 3 Flash Preview measured |
| LMArena Text: math | Not measured | 1389 | Only gpt-oss-120b measured |
| LMArena Text: mathematical work | Not measured | 1386 | Only gpt-oss-120b measured |
| Neither model has a result on the other 2 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index70
| Benchmark | Gemini 3 Flash Preview | gpt-oss-120b | Leader |
|---|---|---|---|
| MMLU Pro | 88.6% | 79.2% | Gemini 3 Flash Preview |
| LegalBench (Vals AI) | 86.9% | 75.9% | Gemini 3 Flash Preview |
| CaseLaw (Vals AI) | 55.8% | 48.8% | Gemini 3 Flash Preview |
| CorpFin (Vals AI) | 66.4% | 58.2% | Gemini 3 Flash Preview |
| TaxEval (Vals AI) | 73.9% | 71.6% | Gemini 3 Flash Preview |
| MortgageTax (Vals AI) | 68.7% | Not measured | Only Gemini 3 Flash Preview measured |
| MedQA (Vals AI) | 95.8% | 91.4% | Gemini 3 Flash Preview |
| MedCode (Vals AI) | 55.9% | Not measured | Only Gemini 3 Flash Preview measured |
| MMLU Pro (Artificial Analysis run) | 89.0% | 80.8% | Gemini 3 Flash Preview |
| SimpleQA Verified | 66.8% | Not measured | Only Gemini 3 Flash Preview measured |
| GeoBench | 88.0% | Not measured | Only Gemini 3 Flash Preview measured |
| LMArena Text: science | Not measured | 1382 | Only gpt-oss-120b measured |
| LMArena Text: medicine and healthcare | Not measured | 1388 | Only gpt-oss-120b measured |
| LMArena Text: legal and government | Not measured | 1355 | Only gpt-oss-120b measured |
| LMArena Text: business and finance | Not measured | 1359 | Only gpt-oss-120b measured |
| Neither model has a result on the other 2 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Gemini 3 Flash Preview | gpt-oss-120b | Leader |
|---|---|---|---|
| Design Arena: websites | 1196 | 968 | Gemini 3 Flash Preview |
| Design Arena: UI components | Not measured | 927 | Only gpt-oss-120b measured |
| Design Arena: game dev | 1166 | 992 | Gemini 3 Flash Preview |
| Design Arena: data viz | Not measured | 987 | Only gpt-oss-120b measured |
| Design Arena: 3D | 1184 | 901 | Gemini 3 Flash Preview |
| Design Arena: all code categories | 1189 | 963 | Gemini 3 Flash Preview |
| Neither model has a result on the other 3 boards here | |||
GeneralLike-for-likePublic boards, shown as published, kept out of the index40
| Benchmark | Gemini 3 Flash Preview | gpt-oss-120b | 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% | 69.0% | Gemini 3 Flash Preview |
| Long context reasoning (AA-LCR) | 78.0% | 52.0% | Gemini 3 Flash Preview |
| DTBench | 89.1% | 76.3% | Gemini 3 Flash Preview |
| LMCA | 43.1% | 22.1% | Gemini 3 Flash Preview |
| Fiction.LiveBench | Not measured | 44.4% | Only gpt-oss-120b measured |
| Creative writing (Lech Mazur) | Not measured | 77.1% | Only gpt-oss-120b measured |
| Surface Evolver Bench | Not measured | 25.0% | Only gpt-oss-120b measured |
| LMArena Text | Not measured | 1366 | Only gpt-oss-120b measured |
| LMArena Text: instruction following | Not measured | 1318 | Only gpt-oss-120b measured |
| LMArena Text: creative writing | Not measured | 1274 | Only gpt-oss-120b measured |
| LMArena Text: English | Not measured | 1375 | Only gpt-oss-120b measured |
| LMArena Text: non-English | Not measured | 1351 | Only gpt-oss-120b measured |
| LMArena Text: Chinese | Not measured | 1385 | Only gpt-oss-120b measured |
| LMArena Text: German | Not measured | 1353 | Only gpt-oss-120b measured |
| LMArena Text: Japanese | Not measured | 1331 | Only gpt-oss-120b measured |
| LMArena Text: Korean | Not measured | 1282 | Only gpt-oss-120b measured |
| LMArena Text: French | Not measured | 1370 | Only gpt-oss-120b measured |
| LMArena Text: Spanish | Not measured | 1389 | Only gpt-oss-120b measured |
| LMArena Text: Russian | Not measured | 1343 | Only gpt-oss-120b measured |
| LMArena Text: Polish | Not measured | 1353 | Only gpt-oss-120b measured |
| LMArena Text: multi-turn | Not measured | 1340 | Only gpt-oss-120b measured |
| LMArena Text: longer queries | Not measured | 1319 | Only gpt-oss-120b measured |
| LMArena Text: writing and language | Not measured | 1306 | Only gpt-oss-120b measured |
| LMArena Text: entertainment and media | Not measured | 1292 | Only gpt-oss-120b measured |
| Neither model has a result on the other 19 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3 Flash Preview | gpt-oss-120b | 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
gpt-oss-120b costs less
Repository review
50K input + 3K output tokens
gpt-oss-120b costs less
Agent loop
200K input + 10K output tokens
gpt-oss-120b 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 gpt-oss-120b |
|---|---|---|
| Maker | OpenAI | |
| Weights | No public weights listed | Open weights |
| Released | December 17, 2025 | August 5, 2025 |
| Context window | 1.05M | 131K |
| Input $/Mtok | $0.50 | $0.15 |
| Output $/Mtok | $3.00 | $0.60 |
| Coding index | 75.8 | 34.5 |
| Independent measurements behind it | 1 | 2 |
| Cost per solved task | $0.37 | $0.51 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 3 Flash Preview better than gpt-oss-120b for coding?
Pick Gemini 3 Flash Preview for coding: it scores 75.8 on the Vibe Coding Index against 34.5 for gpt-oss-120b, though on 1 benchmark against 2. Pick gpt-oss-120b when output tokens cost 5.0x less.
Which is cheaper, Gemini 3 Flash Preview or gpt-oss-120b?
Gemini 3 Flash Preview costs $0.50 per million input tokens and $3.00 per million output tokens; gpt-oss-120b costs $0.15 and $0.60. Per solved SWE-bench Verified task, Gemini 3 Flash Preview costs $0.37 and gpt-oss-120b $0.51.
Which has the bigger context window, Gemini 3 Flash Preview or gpt-oss-120b?
Gemini 3 Flash Preview, with 1.05M tokens against 131K.
How many benchmarks is the Gemini 3 Flash Preview vs gpt-oss-120b comparison based on?
37 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 gpt-oss-120b's on 2. Where only one model has a result, the page says so instead of naming a winner.