Gemini 3 Flash Preview vs GPT-5.6 Sol
Updated October 21, 2026. 56 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 Flash Preview and GPT-5.6 Sol are level for coding, 75.8 against 76.7 on the Vibe Coding Index, so price and context decide.
Pick Gemini 3 Flash Preview when output tokens cost 6.7x less, or when a solved task costs $0.37 against $1.20. Pick GPT-5.6 Sol when the context window is larger, 1.05M against 1.05M tokens, or when what matters is SWE-bench Verified (Vals AI) or Vibe Code Bench (Vals AI), where it leads.
- Shared results
- 56
- Gemini 3 Flash Preview only
- 13
- GPT-5.6 Sol only
- 80
- 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
No call
Level: 75.8 against 76.7, inside 2 points.
1 and 2 benchmarks behind the scores
Intelligence
AA Intelligence Index
GPT-5.6 Sol
GPT-5.6 Sol leads, 47.0 against 26.3.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only GPT-5.6 Sol has a AA Agentic Index result, 50.2.
Directional only
Reasoning
GPQA Diamond
GPT-5.6 Sol
GPT-5.6 Sol leads, 95.2% against 87.9%.
Same board, both measured
Math
AIME
No call
Only Gemini 3 Flash Preview has a AIME result, 95.6%.
Directional only
Knowledge
MMLU Pro
GPT-5.6 Sol
GPT-5.6 Sol leads, 89.1% against 88.6%.
Same board, both measured
Web design
Design Arena: websites
GPT-5.6 Sol
GPT-5.6 Sol leads, 1321 against 1196.
Same board, both measured
Long documents
Listed context window
GPT-5.6 Sol
GPT-5.6 Sol takes 1.05M tokens against 1.05M.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
Gemini 3 Flash Preview
Gemini 3 Flash Preview $0.0020, GPT-5.6 Sol $0.014 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-5.6 Sol $1.20.
Published attempt cost and pass rate
At a glance
- Coding index
- Gemini 3 Flash Preview 75.8 from 1 benchmark, GPT-5.6 Sol 76.7 from 2 benchmarks.
- Widest category
- Math, 44.0 points apart on average over 4 shared benchmarks.
- Widest single gap
- ProofBench: Gemini 3 Flash Preview 15.0% against GPT-5.6 Sol 83.0%, 68.0 points apart on a 0 to 100 scale.
- Output price
- Gemini 3 Flash Preview $3.00 against GPT-5.6 Sol $20.00 per million output tokens, 6.7x apart.
- Context window
- Gemini 3 Flash Preview takes 1.05M tokens, GPT-5.6 Sol 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 | Gemini 3 Flash Preview | Bars | GPT-5.6 Sol | Ties |
|---|---|---|---|---|
| Coding | 1 | 9 | ||
| Intelligence | 0 | 1 | ||
| Agentic work | 0 | 13 | ||
| Reasoning | 0 | 10 | ||
| Math | 0 | 4 | ||
| Knowledge | 3 | 4 | ||
| Web design | 0 | 4 | ||
| General | 1 | 6 | ||
| All shared boards | 5 | 51 |
CodingLike-for-likeFour of these boards feed the Vibe Coding Index19
| Benchmark | Gemini 3 Flash Preview | GPT-5.6 Sol | Leader |
|---|---|---|---|
| SWE-bench Verified | 75.8% | Not measured | Only Gemini 3 Flash Preview measured |
| LiveBench coding | Not measured | 89.7% | Only GPT-5.6 Sol measured |
| LMArena WebDev | Not measured | 1616 | Only GPT-5.6 Sol measured |
| AA Coding Index | Not measured | 77.4 | Only GPT-5.6 Sol measured |
| LiveCodeBench (Vals AI) | 85.6% | 82.6% | Gemini 3 Flash Preview |
| SWE-bench Verified (Vals AI) | 75.0% | 96.2% | GPT-5.6 Sol |
| Terminal-Bench 4 (Vals AI) | Not measured | 37.9% | Only GPT-5.6 Sol measured |
| Vibe Code Bench (Vals AI) | 20.2% | 80.5% | GPT-5.6 Sol |
| Code migration (Vals AI) | 6.4% | 52.9% | GPT-5.6 Sol |
| ProgramBench (Vals AI) | 0.0% | 1.5% | GPT-5.6 Sol |
| IOI (Vals AI) | Not measured | 91.2% | Only GPT-5.6 Sol measured |
| Terminal-Bench 2.1 (Vals AI) | 53.9% | 85.8% | GPT-5.6 Sol |
| Vibe Code Bench 1-100 (Vals AI) | Not measured | 20.0% | Only GPT-5.6 Sol measured |
| SkillsBench (Vals AI) | Not measured | 54.1% | Only GPT-5.6 Sol measured |
| CyberBench (Vals AI) | Not measured | 76.3% | Only GPT-5.6 Sol measured |
| LiveCodeBench (Artificial Analysis run) | 90.8% | Not measured | Only Gemini 3 Flash Preview measured |
| SciCode | Not measured | 57.8% | Only GPT-5.6 Sol measured |
| Terminal-Bench Hard (Artificial Analysis run) | 38.6% | 65.9% | GPT-5.6 Sol |
| Terminal-Bench | 64.3% | Not measured | Only Gemini 3 Flash Preview measured |
| FrontierCode | Not measured | 47.5% | Only GPT-5.6 Sol measured |
| FrontierSWE | Not measured | 32.2% | Only GPT-5.6 Sol measured |
| GSO-Bench | 9.8% | 76.5% | GPT-5.6 Sol |
| WeirdML | 61.6% | 88.8% | GPT-5.6 Sol |
| MirrorCode | Not measured | 20.0% | Only GPT-5.6 Sol measured |
| ALE-Bench | 1367.2 | 2176.9 | GPT-5.6 Sol |
| LMArena Text: coding | Not measured | 1496 | Only GPT-5.6 Sol measured |
| LMArena Text: software and IT | Not measured | 1489 | Only GPT-5.6 Sol measured |
| LMArena WebDev: React | Not measured | 1620 | Only GPT-5.6 Sol measured |
| LMArena WebDev: HTML | Not measured | 1618 | Only GPT-5.6 Sol measured |
| LMArena WebDev: from an image | Not measured | 1609 | Only GPT-5.6 Sol measured |
| Neither model has a result on the other 8 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index01
| Benchmark | Gemini 3 Flash Preview | GPT-5.6 Sol | Leader |
|---|---|---|---|
| AA Intelligence Index | 26.3 | 47.0 | GPT-5.6 Sol |
| Epoch Capabilities Index | Not measured | 162.8 | Only GPT-5.6 Sol measured |
Agentic workLike-for-likePublic boards, shown as published, kept out of the index013
| Benchmark | Gemini 3 Flash Preview | GPT-5.6 Sol | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 50.2 | Only GPT-5.6 Sol measured |
| Design Arena: agents building web apps | 1111 | 1245 | GPT-5.6 Sol |
| Design Arena: agents building full-stack apps | 1063 | 1261 | GPT-5.6 Sol |
| Design Arena: agents building mobile apps | 1090 | 1249 | GPT-5.6 Sol |
| Design Arena: agents building Android apps | 1056 | 1246 | GPT-5.6 Sol |
| Design Arena: agents building Godot games | 1161 | 1260 | GPT-5.6 Sol |
| Design Arena: agents building games | Not measured | 1267 | Only GPT-5.6 Sol measured |
| Design Arena: HTML slides | Not measured | 1286 | Only GPT-5.6 Sol measured |
| Design Arena: PowerPoint slides | 1036 | 1240 | GPT-5.6 Sol |
| LiveBench research | Not measured | 54.5% | Only GPT-5.6 Sol measured |
| LiveBench browser | Not measured | 88.0% | Only GPT-5.6 Sol measured |
| LiveBench long agentic | Not measured | 48.5% | Only GPT-5.6 Sol measured |
| SREBench (Vals AI) | Not measured | 30.5% | Only GPT-5.6 Sol measured |
| Finance Agent (Vals AI) | 42.5% | 53.8% | GPT-5.6 Sol |
| Tax Agent Bench (Vals AI) | 11.8% | 31.1% | GPT-5.6 Sol |
| Legal Research Bench (Vals AI) | 18.3% | 48.1% | GPT-5.6 Sol |
| Excel Modeling Benchmark (Vals AI) | 26.0% | 72.3% | GPT-5.6 Sol |
| BioMysteryBench (Vals AI) | Not measured | 71.1% | Only GPT-5.6 Sol measured |
| Terminal-Bench-Science (Vals AI) | Not measured | 20.0% | Only GPT-5.6 Sol measured |
| Vals Science Index | Not measured | 41.5% | Only GPT-5.6 Sol measured |
| Time Horizon Index (Vals AI) | Not measured | 23.8% | Only GPT-5.6 Sol measured |
| CUA-bench (Vals AI) | Not measured | 8.3% | Only GPT-5.6 Sol measured |
| τ²-Bench Telecom | 80.4% | 85.1% | GPT-5.6 Sol |
| OSWorld 2.0 | Not measured | 27.3% | Only GPT-5.6 Sol measured |
| BALROG | 48.1% | 60.0% | GPT-5.6 Sol |
| DeepResearch Bench | 49.8% | Not measured | Only Gemini 3 Flash Preview measured |
| PostTrainBench | Not measured | 36.2% | Only GPT-5.6 Sol measured |
| Vending-Bench 2 | $3,635 | $9,619 | GPT-5.6 Sol |
| LMArena Search | Not measured | 1261 | Only GPT-5.6 Sol measured |
| Neither model has a result on the other 10 boards here | |||
ReasoningLike-for-likePublic boards, shown as published, kept out of the index010
| Benchmark | Gemini 3 Flash Preview | GPT-5.6 Sol | Leader |
|---|---|---|---|
| GPQA Diamond | 87.9% | 95.2% | GPT-5.6 Sol |
| LiveBench reasoning | Not measured | 91.7% | Only GPT-5.6 Sol measured |
| MysteryMechanism (Vals AI) | Not measured | 33.3% | Only GPT-5.6 Sol measured |
| MMMU Pro (Vals AI) | 87.6% | 88.8% | GPT-5.6 Sol |
| GPQA Diamond (Artificial Analysis run) | 89.8% | 94.1% | GPT-5.6 Sol |
| Humanity's Last Exam (Artificial Analysis run) | 36.6% | 49.5% | GPT-5.6 Sol |
| GPQA Diamond (Epoch AI run) | 89.4% | 93.5% | GPT-5.6 Sol |
| ARC-AGI | 84.7% | 97.5% | GPT-5.6 Sol |
| ARC-AGI-2 | 33.6% | 92.5% | GPT-5.6 Sol |
| SimpleBench | 61.1% | 64.8% | GPT-5.6 Sol |
| Chess puzzles | 39.0% | 59.0% | GPT-5.6 Sol |
| Mystery game puzzles | 26.0% | 58.0% | GPT-5.6 Sol |
| EBR-bench | Not measured | 44.8% | Only GPT-5.6 Sol measured |
| VPCT | 72.6% | Not measured | Only Gemini 3 Flash Preview measured |
| LMArena Text: hard prompts | Not measured | 1483 | Only GPT-5.6 Sol measured |
| LMArena Text: expert | Not measured | 1517 | Only GPT-5.6 Sol measured |
| LMArena Text: hard prompts in English | Not measured | 1477 | Only GPT-5.6 Sol measured |
| LMArena Vision: diagrams | Not measured | 1305 | Only GPT-5.6 Sol measured |
| LMArena Vision: homework | Not measured | 1305 | Only GPT-5.6 Sol measured |
| Neither model has a result on the other 2 boards here | |||
MathLike-for-likePublic boards, shown as published, kept out of the index04
| Benchmark | Gemini 3 Flash Preview | GPT-5.6 Sol | Leader |
|---|---|---|---|
| AIME | 95.6% | Not measured | Only Gemini 3 Flash Preview measured |
| MGSM (Vals AI) | 93.3% | Not measured | Only Gemini 3 Flash Preview measured |
| 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% | 100.0% | GPT-5.6 Sol |
| FrontierMath, tiers 1 to 3 | 51.2% | 89.1% | GPT-5.6 Sol |
| FrontierMath, tier 4 | 17.1% | 82.9% | GPT-5.6 Sol |
| ProofBench | 15.0% | 83.0% | GPT-5.6 Sol |
| LMArena Text: math | Not measured | 1473 | Only GPT-5.6 Sol measured |
| LMArena Text: mathematical work | Not measured | 1496 | Only GPT-5.6 Sol measured |
| Neither model has a result on the other 3 boards here | |||
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index34
| Benchmark | Gemini 3 Flash Preview | GPT-5.6 Sol | Leader |
|---|---|---|---|
| MMLU Pro | 88.6% | 89.1% | GPT-5.6 Sol |
| LegalBench (Vals AI) | 86.9% | 87.0% | GPT-5.6 Sol |
| CaseLaw (Vals AI) | 55.8% | Not measured | Only Gemini 3 Flash Preview measured |
| CorpFin (Vals AI) | 66.4% | 64.4% | Gemini 3 Flash Preview |
| TaxEval (Vals AI) | 73.9% | 74.8% | GPT-5.6 Sol |
| MortgageTax (Vals AI) | 68.7% | 67.3% | Gemini 3 Flash Preview |
| MedQA (Vals AI) | 95.8% | Not measured | Only Gemini 3 Flash Preview measured |
| MedCode (Vals AI) | 55.9% | 44.0% | Gemini 3 Flash Preview |
| MMLU Pro (Artificial Analysis run) | 89.0% | Not measured | Only Gemini 3 Flash Preview measured |
| SimpleQA Verified | 66.8% | 69.7% | GPT-5.6 Sol |
| GeoBench | 88.0% | Not measured | Only Gemini 3 Flash Preview measured |
| LMArena Text: science | Not measured | 1455 | Only GPT-5.6 Sol measured |
| LMArena Text: medicine and healthcare | Not measured | 1431 | Only GPT-5.6 Sol measured |
| LMArena Text: legal and government | Not measured | 1476 | Only GPT-5.6 Sol measured |
| LMArena Text: business and finance | Not measured | 1457 | Only GPT-5.6 Sol measured |
| Neither model has a result on the other 2 boards here | |||
Web designLike-for-likePublic boards, shown as published, kept out of the index04
| Benchmark | Gemini 3 Flash Preview | GPT-5.6 Sol | Leader |
|---|---|---|---|
| Design Arena: websites | 1196 | 1321 | GPT-5.6 Sol |
| Design Arena: UI components | Not measured | 1338 | Only GPT-5.6 Sol measured |
| Design Arena: game dev | 1166 | 1368 | GPT-5.6 Sol |
| Design Arena: data viz | Not measured | 1323 | Only GPT-5.6 Sol measured |
| Design Arena: 3D | 1184 | 1385 | GPT-5.6 Sol |
| Design Arena: all code categories | 1189 | 1341 | GPT-5.6 Sol |
| Design Arena: SVG | Not measured | 1316 | Only GPT-5.6 Sol measured |
| Design Arena: ASCII art | Not measured | 1302 | Only GPT-5.6 Sol measured |
| LiveBench design | Not measured | 81.6% | Only GPT-5.6 Sol measured |
GeneralLike-for-likePublic boards, shown as published, kept out of the index16
| Benchmark | Gemini 3 Flash Preview | GPT-5.6 Sol | Leader |
|---|---|---|---|
| LiveBench data analysis | Not measured | 79.8% | Only GPT-5.6 Sol measured |
| Public Benefits Bench (Vals AI) | Not measured | 66.5% | Only GPT-5.6 Sol measured |
| SAGE (Vals AI) | 51.8% | 52.6% | GPT-5.6 Sol |
| MedScribe (Vals AI) | 69.9% | 85.2% | GPT-5.6 Sol |
| Vals Multimodal Index | 52.2% | 72.6% | GPT-5.6 Sol |
| IFBench | 78.0% | 72.7% | Gemini 3 Flash Preview |
| Long context reasoning (AA-LCR) | 78.0% | 84.0% | GPT-5.6 Sol |
| DTBench | 89.1% | 95.7% | GPT-5.6 Sol |
| LMCA | 43.1% | 58.5% | GPT-5.6 Sol |
| Surface Evolver Bench | Not measured | 93.1% | Only GPT-5.6 Sol measured |
| Furniture assembly | Not measured | 56.7% | Only GPT-5.6 Sol measured |
| LMArena Text | Not measured | 1457 | Only GPT-5.6 Sol measured |
| LMArena Text: instruction following | Not measured | 1483 | Only GPT-5.6 Sol measured |
| LMArena Text: creative writing | Not measured | 1449 | Only GPT-5.6 Sol measured |
| LMArena Vision | Not measured | 1281 | Only GPT-5.6 Sol measured |
| LMArena Text: English | Not measured | 1457 | Only GPT-5.6 Sol measured |
| LMArena Text: non-English | Not measured | 1451 | Only GPT-5.6 Sol measured |
| LMArena Text: Chinese | Not measured | 1525 | Only GPT-5.6 Sol measured |
| LMArena Text: German | Not measured | 1476 | Only GPT-5.6 Sol measured |
| LMArena Text: Japanese | Not measured | 1472 | Only GPT-5.6 Sol measured |
| LMArena Text: Korean | Not measured | 1442 | Only GPT-5.6 Sol measured |
| LMArena Text: French | Not measured | 1472 | Only GPT-5.6 Sol measured |
| LMArena Text: Spanish | Not measured | 1443 | Only GPT-5.6 Sol measured |
| LMArena Text: Russian | Not measured | 1471 | Only GPT-5.6 Sol measured |
| LMArena Text: Polish | Not measured | 1459 | Only GPT-5.6 Sol measured |
| LMArena Text: multi-turn | Not measured | 1461 | Only GPT-5.6 Sol measured |
| LMArena Text: longer queries | Not measured | 1481 | Only GPT-5.6 Sol measured |
| LMArena Text: writing and language | Not measured | 1462 | Only GPT-5.6 Sol measured |
| LMArena Text: entertainment and media | Not measured | 1450 | Only GPT-5.6 Sol measured |
| LMArena Vision: English | Not measured | 1280 | Only GPT-5.6 Sol measured |
| LMArena Vision: Chinese | Not measured | 1313 | Only GPT-5.6 Sol measured |
| LMArena Vision: reading text | Not measured | 1290 | Only GPT-5.6 Sol measured |
| LMArena Vision: humor | Not measured | 1246 | Only GPT-5.6 Sol measured |
| LMArena Vision: creative writing | Not measured | 1283 | Only GPT-5.6 Sol measured |
| LMArena Document | Not measured | 1483 | Only GPT-5.6 Sol measured |
| Neither model has a result on the other 11 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | Gemini 3 Flash Preview | GPT-5.6 Sol | 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 GPT-5.6 Sol |
|---|---|---|
| Maker | OpenAI | |
| Weights | No public weights listed | No public weights listed |
| Released | December 17, 2025 | July 9, 2026 |
| Context window | 1.05M | 1.05M |
| Input $/Mtok | $0.50 | $4.00 |
| Output $/Mtok | $3.00 | $20.00 |
| Coding index | 75.8 | 76.7 |
| Independent measurements behind it | 1 | 2 |
| Cost per solved task | $0.37 | $1.20 |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is Gemini 3 Flash Preview better than GPT-5.6 Sol for coding?
Gemini 3 Flash Preview and GPT-5.6 Sol are level for coding, 75.8 against 76.7 on the Vibe Coding Index, so price and context decide. Pick Gemini 3 Flash Preview when output tokens cost 6.7x less, or when a solved task costs $0.37 against $1.20. Pick GPT-5.6 Sol when the context window is larger, 1.05M against 1.05M tokens, or when what matters is SWE-bench Verified (Vals AI) or Vibe Code Bench (Vals AI), where it leads.
Which is cheaper, Gemini 3 Flash Preview or GPT-5.6 Sol?
Gemini 3 Flash Preview costs $0.50 per million input tokens and $3.00 per million output tokens; GPT-5.6 Sol costs $4.00 and $20.00. Per solved SWE-bench Verified task, Gemini 3 Flash Preview costs $0.37 and GPT-5.6 Sol $1.20.
Which has the bigger context window, Gemini 3 Flash Preview or GPT-5.6 Sol?
GPT-5.6 Sol, with 1.05M tokens against 1.05M.
How many benchmarks is the Gemini 3 Flash Preview vs GPT-5.6 Sol comparison based on?
56 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-5.6 Sol's on 2. Where only one model has a result, the page says so instead of naming a winner.