BenchLeader

Gemini 3.5 Flash vs GPT-5.6 Sol

Full profiles: Gemini 3.5 Flash (Google) and GPT-5.6 Sol (OpenAI): every benchmark, price and rank.

Updated · Data from 10 sources

As of 25 Oct 2026, GPT-5.6 Sol (max) leads on quality (68.0 vs 63.1 on the BenchLeader Index), but Gemini 3.5 Flash (high) costs 2.4× less, so it is the better buy unless you need the extra quality. Pick Gemini 3.5 Flash for instruction following (74 vs 71); pick GPT-5.6 Sol for maths (71 vs 58).

Which to pick for…

The pick's numbers come first. Category scores on the BenchLeader scale (50 is the average model, 15 points one standard deviation). High confidence means a lead of half a standard deviation or more; under one point is called either.

Use casePickWhyConfidence
CodingGPT-5.6 Sol66 vs 60 category score; SciCode 57.1% vs 53.9%Medium
Agents & tool useGPT-5.6 Sol67 vs 63 category score; τ³-Banking (AA) 44.3% vs 32.2%Medium
MathsGPT-5.6 Sol71 vs 58 category score; FrontierMath Tiers 1–3 89.1% vs 62.8%High
ReasoningGPT-5.6 Sol72 vs 61 category score; GPQA Diamond 93.5% vs 92.8%High
KnowledgeEither65 vs 65 category score; SimpleQA Verified 66.2% vs 69.7%Either
Long documentsGPT-5.6 Sol67 vs 62 category score; AA-LCR 84.0% vs 73.3%Medium
Images and other mediaEither67 vs 67 category score; MMMU-Pro 84.3% vs 83.4%Either
Following instructionsGemini 3.5 Flash74 vs 71 category score; IFBench 76.3% vs 72.7%Medium
Chat quality (human preference)–Only Gemini 3.5 Flash has an Arena rating (67 category score)Not comparable
Lowest costGemini 3.5 Flash$3.38 vs $8.00 per 1M blended; agentic coding session $0.126 vs $0.320–
Fastest first answerGemini 3.5 Flash14.2 s (Gemini 3.5 Flash (high)) vs 69.5 s (GPT-5.6 Sol (max)) to the first answer token–
High volume on a budgetNeither flagshipA smaller model is usually the better fit: Cheapest good LLMs, Fastest LLMs–

Key differences

  • GPT-5.6 Sol (max) leads on quality: 68.0 vs 63.1.
  • Gemini 3.5 Flash (high) is stronger in human preference, instruction following, multimodal.
  • GPT-5.6 Sol (max) is stronger in agents & tools, coding, composite, knowledge, long context, maths, reasoning.
  • Gemini 3.5 Flash (high) is 2.4× cheaper ($3.38 vs $8.00 per 1M blended).
  • Gemini 3.5 Flash (high) streams 2.5× faster (222 vs 89 tokens per second).

At a glance

SpecGemini 3.5 FlashGPT-5.6 Sol
DeveloperGoogleOpenAI
Released19 May 20269 Jul 2026
Context window (tokens)1,048,5761,050,000
Compared atGemini 3.5 Flash (high)GPT-5.6 Sol (max)
Open weightsNoNo
Price in / out / cached input per 1M$1.50 / $9.00 / $0.150$4.00 / $20.00 / $0.400

Category by category

Category scores on the BenchLeader scale: 50 is the average evaluated model, 15 points is one standard deviation. A gap under one point is called level.

CategoryGemini 3.5 Flash (high)GPT-5.6 Sol (max)Leader
Reasoning61.372.4GPT-5.6 Sol
Coding59.865.9GPT-5.6 Sol
Agents & tools63.466.5GPT-5.6 Sol
Maths58.371.0GPT-5.6 Sol
Knowledge65.265.3level
Instruction following74.371.1Gemini 3.5 Flash
Human preference66.8–not comparable
Multimodal66.666.5level
Long context61.667.1GPT-5.6 Sol
Composite65.982.0GPT-5.6 Sol

Where sources disagree

Across the 74 benchmarks both have, Gemini 3.5 Flash leads 12, GPT-5.6 Sol leads 61 and 1 is a tie. Every overall index that rates both puts GPT-5.6 Sol ahead.

Overall indexGemini 3.5 Flash (high)GPT-5.6 Sol (max)Leader
BenchLeader Index63.168.0GPT-5.6 Sol
AA Intelligence Index v4.3.232.647.0GPT-5.6 Sol
Arena Text14771485†GPT-5.6 Sol

Each publisher runs its own tasks, harnesses and effort settings, so their overall verdicts can differ; BenchLeader reconciles them on one scale. † measured at another effort setting of the same model (the publisher did not test the one compared here).

Price, speed and latency

List prices blended at three input tokens per output token. Per-task prices use the token counts on the methodology page; suite cost is what Artificial Analysis paid to run its whole Intelligence Index.

MeasureGemini 3.5 Flash (high)GPT-5.6 Sol (max)
Blended price per 1M tokens$3.38$8.00
Input / output per 1M$1.50 / $9.00$4.00 / $20.00
Cached input per 1M$0.150$0.400
Price per task: chat reply$0.0033$0.0076
Price per task: summarize a 30-page report$0.023$0.060
Price per task: code edit$0.022$0.054
Price per task: agentic coding session$0.126$0.320
Price per task: structured extraction$0.0048$0.012
Cost to run a full benchmark suite$3.69$1.99
Output speed222 tok/s89 tok/s
Time to first answer14.2 s69.5 s
Time to a complete answer16.4 s75.1 s

Per token is not per task: on Artificial Analysis' full suite Gemini 3.5 Flash (high) cost $3.69 and GPT-5.6 Sol (max) $1.99, because Gemini 3.5 Flash (high) used about 4.4× as many tokens for the same work, which a per-token price hides.

Each model is compared at its best-ranked reasoning-effort setting. Gemini 3.5 Flash (high) scores 63.1 and takes 14 s to its first answer token; Gemini 3.5 Flash (medium) scores 62.8 in 12 s, Gemini 3.5 Flash (minimal) scores 56.4 in 1 s. GPT-5.6 Sol (max) scores 68.0 and takes 69 s to its first answer token; GPT-5.6 Sol (xhigh) scores 66.6 in 17 s, GPT-5.6 Sol (high) scores 66.3 in 7 s. Higher effort means more thinking before the answer: better scores, longer waits and more tokens billed. How reasoning effort changes scores and cost.

Every benchmark

146 benchmarks, grouped by category; each name links to the board and its leaders. † measured at another effort setting of the same model, shown for reference and not counted as a win.

MetricPublisherGemini 3.5 Flash (high)GPT-5.6 Sol (max)
BenchLeader IndexBenchLeader63.168.0
Agents & tools scoreBenchLeader63.466.5
Coding scoreBenchLeader59.865.9
Composite scoreBenchLeader65.982.0
Human preference scoreBenchLeader66.8–
Instruction following scoreBenchLeader74.371.1
Knowledge scoreBenchLeader65.265.3
Long context scoreBenchLeader61.667.1
Maths scoreBenchLeader58.371.0
Multimodal scoreBenchLeader66.666.5
Reasoning scoreBenchLeader61.372.4
Blended price $/MBenchLeader$3.38$8.00
Output speedBenchLeader222 tok/s89 tok/s
Time to first answerBenchLeader14.2 s69.5 s
Context windowBenchLeader1,048,576 tokens1,050,000 tokens
Reasoning
GPQA DiamondEpoch AI Benchmarking Hub92.8%93.5%
SimpleBenchSimpleBench76.7%†64.8%†
Arena Hard PromptsArena (LMArena)14951512†
LiveBench 2.0 ReasoningLiveBench–91.7%†
LiveBench 1.0 ReasoningLiveBench82.0%91.7%
GPQA Diamond (AA)Artificial Analysis92.2%94.1%
Humanity's Last Exam (AA)Artificial Analysis42.7%49.5%
GPQA Diamond (Vals)Vals AI92.7%95.2%
EnigmaEvalScale AI SEAL25.4%37.1%†
Kagi LLM BenchmarkKagi LLM Benchmark–67.0%†
ARC-AGI-1ARC Prize92.5%96.5%
ARC-AGI-2ARC Prize72.1%92.5%
ARC-AGI-3ARC Prize–7.8%
CritPtArtificial Analysis13.1%32.3%
MysteryMechanismVals AI–33.3%
Chess PuzzlesEpoch AI Benchmarking Hub45.0%59.0%
Mystery Game PuzzlesEpoch AI Benchmarking Hub32.0%58.0%
LMCAEpoch AI Benchmarking Hub47.1%58.4%
DTBenchEpoch AI Benchmarking Hub94.7%95.5%
ForecastBenchForecastBench64.3%†65.5%
BTF-3Epoch AI Benchmarking Hub–13.7%
Coding
SWE-bench Verified (Epoch)Epoch AI Benchmarking Hub79.3%–
SciCodeSciCode53.9%57.1%
WeirdMLWeirdML62.6%87.0%
FrontierCodeCognition–47.5%†
Show all 146 benchmarks
MetricPublisherGemini 3.5 Flash (high)GPT-5.6 Sol (max)
Coding
GSO-BenchGSO-Bench–76.5%†
Arena CodingArena (LMArena)15081534†
Arena WebDevArena (LMArena)14991615†
LiveBench 2.0 CodingLiveBench–89.7%†
LiveBench 1.0 CodingLiveBench78.2%83.9%
LiveCodeBenchVals AI87.6%82.6%
IOIVals AI–91.2%
SWE-bench (Vals)Vals AI78.8%96.2%
Code MigrationVals AI26.8%52.9%
ProgramBenchVals AI0.0%1.5%
Vibe Code Bench 1-100Vals AI–20.0%
Vibe Code Bench v1.1Vals AI48.7%80.5%
SWE Atlas: Codebase QnAScale AI SEAL–46.0%†
SWE Atlas: Test WritingScale AI SEAL–45.9%†
MirrorCodeEpoch AI Benchmarking Hub–20.0%†
Surface Evolver BenchEpoch AI Benchmarking Hub58.1%†93.1%†
DeepSWE v1.1Epoch AI Benchmarking Hub36.1%72.7%
CursorBenchCursor–41.7%
ALE-BenchEpoch AI Benchmarking Hub911.02176.9
FrontierSWEEpoch AI Benchmarking Hub–32.2%
Terminal-Bench 4.0 (AA)Artificial Analysis6.6%39.9%
Terminal-Bench 2.1 (AA)Artificial Analysis78.7%88.0%
Startrise FrontendStartrise–66.2%†
Agents & tools
Terminal-BenchTerminal-Bench–37.3%
OSWorld-Verified 2.0OSWorld–27.3%
APEX-AgentsMercor27.5%†–
Arena AgentArena (LMArena)–6.1†
LiveBench Long AgenticLiveBench–48.5%†
LiveBench BrowserLiveBench–88.0%†
LiveBench Agentic CodingLiveBench49.0%56.2%
Terminal-Bench HardArtificial Analysis40.9%65.9%
τ²-Bench Telecom (AA)Artificial Analysis95.3%85.1%
Terminal-Bench 2.1 (Vals)Vals AI74.2%85.8%
MCP AtlasScale AI SEAL83.6%–
HiL-BenchScale AI SEAL27.7%†32.3%†
τ³-bench Bankingτ²-bench–46.9%†
τ³-Banking (AA)Artificial Analysis32.2%44.3%
ITBench SRE (AA)Artificial Analysis40.4%56.2%
Analyst Agent (AA)Artificial Analysis45.0%47.5%
APEX-Agents (AA)Artificial Analysis47.0%–
CUA-benchVals AI–8.3%
CyberBenchVals AI–76.3%
Finance Agent v2Vals AI57.9%53.8%
Harvey's Legal Agent Benchmark v1Vals AI2.5%2.5%
Legal Research BenchVals AI30.8%48.1%
SkillsBenchVals AI52.7%54.1%
SREBenchVals AI–30.5%
Tax Agent BenchVals AI21.6%31.1%
Terminal-Bench 2.0 (Vals)Vals AI67.4%–
Terminal-Bench 4.0 (Vals)Vals AI6.1%37.9%
Terminal-Bench ScienceVals AI5.7%20.0%
Time Horizon Index: KSPVals AI–23.8%
Web Search IndexVals AI37.0%43.6%
Arena SearchArena (LMArena)–1258†
BALROGBALROG–60.0%
PostTrainBenchEpoch AI Benchmarking Hub–36.2%
GBAEvalEpoch AI Benchmarking Hub6.7%†52.6%†
Vending-Bench 2Andon Labs5396.4†9619.4†
AutomationBenchArtificial Analysis42.1%60.1%
GDP.pdf (AA)Artificial Analysis19.8%27.2%
EnterpriseOps-GymArtificial Analysis50.1%42.9%
AA-Briefcase v1.1Artificial Analysis8741479
Terminal-Bench-Science 0.1 (AA)Artificial Analysis–22.4%
FACTS SearchGoogle64.3%†88.5%†
Maths
FrontierMath Tiers 1–3Epoch AI Benchmarking Hub62.8%89.1%
FrontierMath Tier 4Epoch AI Benchmarking Hub26.8%82.9%
OTIS Mock AIMEEpoch AI Benchmarking Hub95.6%100.0%
ProofBenchVals AI31.0%83.0%
LiveBench MathematicsLiveBench88.2%96.2%
AIME 2026MathArena95.0%†–
HMMT February 2026MathArena95.5%†–
MathArena ApexMathArena32.3%†–
Arena MathsArena (LMArena)14971496†
Knowledge
SimpleQA VerifiedEpoch AI Benchmarking Hub66.2%69.7%
LiveBench 2.0 Data AnalysisLiveBench–79.8%†
LiveBench ResearchLiveBench–54.5%†
LiveBench 1.0 Data AnalysisLiveBench64.9%79.8%
AA-OmniscienceArtificial Analysis21.222.0
MMLU-ProVals AI89.5%89.1%
LegalBenchVals AI83.6%87.0%
CorpFinVals AI64.7%64.4%
TaxEvalVals AI74.4%74.8%
PRBench FinanceScale AI SEAL–50.5%
PRBench LegalScale AI SEAL–50.5%
BioMysteryBenchVals AI–71.1%
Excel Modeling BenchmarkVals AI63.5%72.3%
MedCodeVals AI55.8%44.0%
MedScribeVals AI76.6%85.2%
Public Benefits Bench v1.1Vals AI59.5%66.5%
DrugDiscoveryBenchScale AI SEAL50.0%56.5%
EBR-benchEpoch AI Benchmarking Hub4.8%44.8%
GDP.pdfEpoch AI Benchmarking Hub14.0%†30.7%
AA-Omniscience: accuracyArtificial Analysis51.4%59.4%
AA-Omniscience: non-hallucinationArtificial Analysis37.8%7.8%
Instruction following
LiveBench LanguageLiveBench84.6%87.7%
LiveBench Instruction FollowingLiveBench75.6%71.8%
IFBenchArtificial Analysis76.3%72.7%
Arena Instruction FollowingArena (LMArena)14651491†
Human preference
Arena TextArena (LMArena)14771485†
EQ-Bench 4EQ-Bench1081†1240†
Arena Creative WritingArena (LMArena)14641470†
Arena Multi-turnArena (LMArena)14801490†
Arena Longer QueriesArena (LMArena)14821499†
Multimodal
Arena VisionArena (LMArena)13081281†
LiveBench DesignLiveBench–81.6%†
MMMU-ProArtificial Analysis84.3%83.4%
MMMU-Pro (Vals)Vals AI88.3%88.8%
MortgageTaxVals AI68.1%67.3%
SAGEVals AI49.9%52.6%
Blueprint-Bench 2Epoch AI Benchmarking Hub33.6%†33.6%†
Long context
AA-LCRArtificial Analysis73.3%84.0%
Arena DocumentArena (LMArena)14531489†
MLCRArtificial Analysis10.0%30.0%
Composite
Epoch Capabilities IndexEpoch AI Benchmarking Hub154.9†162.8†
LiveBench 2.0LiveBench–76.3%†
LiveBench 1.0LiveBench74.6%81.0%
AA Intelligence Index v4.3.2Artificial Analysis32.647.0
Vals RSI IndexVals AI–23.9%
Vals Science IndexVals AI–41.5%
Vals Multimodal IndexVals AI62.9%72.6%
Safety & honesty
FORTRESSScale AI SEAL–20.1%†

Data as of 2026-10-25. Best configuration of each model; every score links to its source on the model pages.

What changed

  • GPT-5.6 Sol (max): 1 new result (AA-Briefcase v1.1).
  • Gemini 3.5 Flash (high): 1 new result (Harvey's Legal Agent Benchmark v1).
  • GPT-5.6 Sol (max): 3 new results (Harvey's Legal Agent Benchmark v1, Vals RSI Index, Vals Science Index).
  • Gemini 3.5 Flash (high): 1 score revision.
  • GPT-5.6 Sol (max): 1 score revision.
  • GPT-5.6 Sol (max): 1 new result (ForecastBench).
  • Gemini 3.5 Flash (high): BenchLeader Index 62.5 → 63.2.
  • Gemini 3.5 Flash (high): 3 new results (GDPval-AA v2.1, AA-Omniscience: accuracy, AA-Omniscience: non-hallucination).
  • GPT-5.6 Sol (max): 5 new results (AutomationBench, GDP.pdf (AA), MLCR…).
  • Gemini 3.5 Flash (high): 1 score revision.

Rankings: Best LLM overall · Best LLM for agents · Best cheap LLMs

Gemini 3.5 Flash vs GPT-5.6 Sol: questions

Is Gemini 3.5 Flash better than GPT-5.6 Sol?
GPT-5.6 Sol (max) leads on quality: 68.0 vs 63.1. The BenchLeader Index combines every independent quality benchmark; GPT-5.6 Sol (max) is ahead overall as of 2026-10-25, but check the category scores for your use.
Which is cheaper, Gemini 3.5 Flash or GPT-5.6 Sol, and will that change?
Gemini 3.5 Flash is cheaper today: $3.38 against $8.00 per million tokens, blended at three input tokens per output token. No price change has been announced for either.
Is Gemini 3.5 Flash better than GPT-5.6 Sol for coding?
GPT-5.6 Sol scores higher in coding (66 vs 60 on the category index, where 50 is average). On LiveCodeBench, the top shared coding benchmark, it is 87.6% for Gemini 3.5 Flash against 82.6% for GPT-5.6 Sol.
Is Gemini 3.5 Flash better than GPT-5.6 Sol for agents and tool use?
GPT-5.6 Sol scores higher in agentic tasks (67 vs 63 on the category index, where 50 is average). On τ³-Banking (AA), the top shared agents & tools benchmark, it is 32.2% for Gemini 3.5 Flash against 44.3% for GPT-5.6 Sol.
Which is better for long documents?
GPT-5.6 Sol scores higher on long-context benchmarks (67 vs 62). Both take about 1.1M tokens: Gemini 3.5 Flash 1,048,576, GPT-5.6 Sol 1,050,000.
Which has lower latency?
Gemini 3.5 Flash (high) answers first: 14.2 s against 69.5 s to the first answer token, as Artificial Analysis measures it. Reasoning effort drives most of this: a higher setting thinks longer before it answers.
Which is faster, Gemini 3.5 Flash or GPT-5.6 Sol?
Gemini 3.5 Flash streams faster: 222 against 89 output tokens per second.
Do independent benchmarks agree on Gemini 3.5 Flash vs GPT-5.6 Sol?
Across the 74 benchmarks both have, Gemini 3.5 Flash leads 12, GPT-5.6 Sol leads 61 and 1 is a tie. Every overall index that rates both puts GPT-5.6 Sol ahead.
When was GPT-5.6 Sol released?
GPT-5.6 Sol was released on 9 Jul 2026.