BenchLeader

Gemini 3.5 Flash vs Kimi K3.1 Pro

Full profiles: Gemini 3.5 Flash (Google) and Kimi K3.1 Pro (Moonshot AI): every benchmark, price and rank.

Updated · Data from 9 sources

As of 24 Oct 2026, Gemini 3.5 Flash (high) and Kimi K3.1 Pro are neck and neck on quality (63.1 vs 66.8 on the BenchLeader Index, inside the ±6.8 margin of error), and Gemini 3.5 Flash (high) costs 1.2× less, which makes it the better buy for most workloads. Kimi K3.1 Pro leads in every category we measure both in.

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
Agents & tool useKimi K3.1 Pro67 vs 63 category score; AutomationBench 73.3% vs 42.1%Medium
ReasoningKimi K3.1 Pro81 vs 61 category score; CritPt 24.6% vs 13.1%High
KnowledgeKimi K3.1 Pro75 vs 65 category score; AA-Omniscience 29.5 vs 21.2High
Long documentsKimi K3.1 Pro68 vs 62 category score; AA-LCR 86.3% vs 73.3%Medium
Images and other mediaEither67 vs 67 category score; MMMU-Pro 84.3% vs 83.9%Either
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 $4.00 per 1M blended; agentic coding session $0.126 vs $0.160–
Fastest first answerGemini 3.5 Flash14.3 s (Gemini 3.5 Flash (high)) vs 27.7 s (Kimi K3.1 Pro) 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

  • Gemini 3.5 Flash (high) and Kimi K3.1 Pro are neck and neck on quality (63.1 vs 66.8, within the ±6.8 margin).
  • Gemini 3.5 Flash (high) is stronger in coding, human preference, instruction following, maths.
  • Kimi K3.1 Pro is stronger in agents & tools, composite, knowledge, long context, multimodal, reasoning.
  • Gemini 3.5 Flash (high) is 1.2× cheaper ($3.38 vs $4.00 per 1M blended).
  • Gemini 3.5 Flash (high) streams 2.8× faster (222 vs 81 tokens per second).

At a glance

SpecGemini 3.5 FlashKimi K3.1 Pro
DeveloperGoogleMoonshot AI
Released19 May 202623 Oct 2026
Context window (tokens)1,048,5761,048,576
Compared atGemini 3.5 Flash (high)Kimi K3.1 Pro
Open weightsNoNo
Price in / out / cached input per 1M$1.50 / $9.00 / $0.150$2.00 / $10.00 / $0.200

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)Kimi K3.1 ProLeader
Reasoning61.381.3Kimi K3.1 Pro
Coding59.9–not comparable
Agents & tools63.467.3Kimi K3.1 Pro
Maths58.3–not comparable
Knowledge65.274.8Kimi K3.1 Pro
Instruction following74.3–not comparable
Human preference66.8–not comparable
Multimodal66.667.0level
Long context61.668.3Kimi K3.1 Pro
Composite65.975.8Kimi K3.1 Pro

Where sources disagree

Across the 12 benchmarks both have, Gemini 3.5 Flash leads 2, Kimi K3.1 Pro leads 10. Every overall index that rates both puts Kimi K3.1 Pro ahead.

Overall indexGemini 3.5 Flash (high)Kimi K3.1 ProLeader
BenchLeader Index63.166.8neck and neck
AA Intelligence Index v4.3.232.655.1Kimi K3.1 Pro

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)Kimi K3.1 Pro
Blended price per 1M tokens$3.38$4.00
Input / output per 1M$1.50 / $9.00$2.00 / $10.00
Cached input per 1M$0.150$0.200
Price per task: chat reply$0.0033$0.0038
Price per task: summarize a 30-page report$0.023$0.030
Price per task: code edit$0.022$0.027
Price per task: agentic coding session$0.126$0.160
Price per task: structured extraction$0.0048$0.0060
Cost to run a full benchmark suite$3.69$2.11
Output speed222 tok/s81 tok/s
Time to first answer14.3 s27.7 s
Time to a complete answer16.6 s33.9 s

Per token is not per task: on Artificial Analysis' full suite Gemini 3.5 Flash (high) cost $3.69 and Kimi K3.1 Pro $2.11, because Gemini 3.5 Flash (high) used about 2.1× 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 13 s, Gemini 3.5 Flash (minimal) scores 56.4 in 1 s. Kimi K3.1 Pro scores 66.8 and takes 28 s to its first answer token. 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

121 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)Kimi K3.1 Pro
BenchLeader IndexBenchLeader63.166.8
Agents & tools scoreBenchLeader63.467.3
Coding scoreBenchLeader59.9–
Composite scoreBenchLeader65.975.8
Human preference scoreBenchLeader66.8–
Instruction following scoreBenchLeader74.3–
Knowledge scoreBenchLeader65.274.8
Long context scoreBenchLeader61.668.3
Maths scoreBenchLeader58.3–
Multimodal scoreBenchLeader66.667.0
Reasoning scoreBenchLeader61.381.3
Blended price $/MBenchLeader$3.38$4.00
Output speedBenchLeader222 tok/s81 tok/s
Time to first answerBenchLeader14.3 s27.7 s
Context windowBenchLeader1,048,576 tokens1,048,576 tokens
Reasoning
GPQA DiamondEpoch AI Benchmarking Hub92.8%–
SimpleBenchSimpleBench76.7%†–
Arena Hard PromptsArena (LMArena)1495–
LiveBench 2.0 ReasoningLiveBench–91.1%
LiveBench 1.0 ReasoningLiveBench82.0%–
GPQA Diamond (AA)Artificial Analysis92.2%–
Humanity's Last Exam (AA)Artificial Analysis42.7%52.5%
GPQA Diamond (Vals)Vals AI92.7%–
EnigmaEvalScale AI SEAL25.4%–
ARC-AGI-1ARC Prize92.5%–
ARC-AGI-2ARC Prize72.1%–
CritPtArtificial Analysis13.1%24.6%
Chess PuzzlesEpoch AI Benchmarking Hub45.0%–
Mystery Game PuzzlesEpoch AI Benchmarking Hub32.0%–
LMCAEpoch AI Benchmarking Hub47.1%–
DTBenchEpoch AI Benchmarking Hub94.7%–
ForecastBenchForecastBench64.3%†–
Coding
SWE-bench Verified (Epoch)Epoch AI Benchmarking Hub79.3%–
SciCodeSciCode53.9%–
WeirdMLWeirdML62.6%–
Arena CodingArena (LMArena)1508–
Arena WebDevArena (LMArena)1499–
LiveBench 2.0 CodingLiveBench–81.8%
LiveBench 1.0 CodingLiveBench78.2%–
SciCode (AA)Artificial Analysis53.9%60.8%
Show all 121 benchmarks
MetricPublisherGemini 3.5 Flash (high)Kimi K3.1 Pro
Coding
LiveCodeBenchVals AI87.6%–
SWE-bench (Vals)Vals AI78.8%–
Code MigrationVals AI26.8%–
ProgramBenchVals AI0.0%–
Vibe Code Bench v1.1Vals AI48.7%–
Surface Evolver BenchEpoch AI Benchmarking Hub58.1%†–
DeepSWE v1.1Epoch AI Benchmarking Hub36.1%–
ALE-BenchEpoch AI Benchmarking Hub911.0–
Terminal-Bench 4.0 (AA)Artificial Analysis6.6%67.2%
Terminal-Bench 2.1 (AA)Artificial Analysis78.7%–
FrontierCode 1.1 (AA)Artificial Analysis–47.1%
Agents & tools
APEX-AgentsMercor27.5%†–
LiveBench Long AgenticLiveBench–49.5%
LiveBench BrowserLiveBench–80.0%
LiveBench Agentic CodingLiveBench49.0%–
Terminal-Bench HardArtificial Analysis40.9%–
τ²-Bench Telecom (AA)Artificial Analysis95.3%–
Terminal-Bench 2.1 (Vals)Vals AI74.2%–
MCP AtlasScale AI SEAL83.6%–
HiL-BenchScale AI SEAL27.7%†–
GDPval-AA v2.1Artificial Analysis–67.3%
τ³-Banking (AA)Artificial Analysis32.2%–
ITBench SRE (AA)Artificial Analysis40.4%–
Analyst Agent (AA)Artificial Analysis45.0%–
APEX-Agents (AA)Artificial Analysis47.0%–
Finance Agent v2Vals AI57.9%–
Harvey's Legal Agent Benchmark v1Vals AI2.5%–
Legal Research BenchVals AI30.8%–
SkillsBenchVals AI52.7%–
Tax Agent BenchVals AI21.6%–
Terminal-Bench 2.0 (Vals)Vals AI67.4%–
Terminal-Bench 4.0 (Vals)Vals AI6.1%–
Terminal-Bench ScienceVals AI5.7%–
Web Search IndexVals AI37.0%–
GBAEvalEpoch AI Benchmarking Hub6.7%†–
Vending-Bench 2Andon Labs5396.4†–
AutomationBenchArtificial Analysis42.1%73.3%
GDP.pdf (AA)Artificial Analysis19.8%31.4%
EnterpriseOps-GymArtificial Analysis50.1%–
AA-Briefcase v1.1Artificial Analysis8741678
CWE-Bench (AA)Artificial Analysis–60.8%
DeepSec-Bench (AA)Artificial Analysis–36.7%
CyberGym end-to-end (AA)Artificial Analysis–94.7%
FACTS SearchGoogle64.3%†–
Maths
FrontierMath Tiers 1–3Epoch AI Benchmarking Hub62.8%–
FrontierMath Tier 4Epoch AI Benchmarking Hub26.8%–
OTIS Mock AIMEEpoch AI Benchmarking Hub95.6%–
ProofBenchVals AI31.0%–
LiveBench MathematicsLiveBench88.2%–
AIME 2026MathArena95.0%†–
HMMT February 2026MathArena95.5%†–
MathArena ApexMathArena32.3%†–
Arena MathsArena (LMArena)1497–
Knowledge
SimpleQA VerifiedEpoch AI Benchmarking Hub66.2%–
LiveBench 2.0 Data AnalysisLiveBench–79.1%
LiveBench ResearchLiveBench–77.9%
LiveBench 1.0 Data AnalysisLiveBench64.9%–
AA-OmniscienceArtificial Analysis21.229.5
MMLU-ProVals AI89.5%–
LegalBenchVals AI83.6%–
CorpFinVals AI64.7%–
TaxEvalVals AI74.4%–
Excel Modeling BenchmarkVals AI63.5%–
MedCodeVals AI55.8%–
MedScribeVals AI76.6%–
Public Benefits Bench v1.1Vals AI59.5%–
DrugDiscoveryBenchScale AI SEAL50.0%–
EBR-benchEpoch AI Benchmarking Hub4.8%–
GDP.pdfEpoch AI Benchmarking Hub14.0%†–
AA-Omniscience: accuracyArtificial Analysis51.4%51.0%
AA-Omniscience: non-hallucinationArtificial Analysis37.8%56.1%
Instruction following
LiveBench LanguageLiveBench84.6%–
LiveBench Instruction FollowingLiveBench75.6%–
IFBenchArtificial Analysis76.3%–
Arena Instruction FollowingArena (LMArena)1465–
Human preference
Arena TextArena (LMArena)1477–
EQ-Bench 4EQ-Bench1087†–
Arena Creative WritingArena (LMArena)1464–
Arena Multi-turnArena (LMArena)1480–
Arena Longer QueriesArena (LMArena)1482–
Multimodal
Arena VisionArena (LMArena)1308–
LiveBench DesignLiveBench–77.8%
MMMU-ProArtificial Analysis84.3%83.9%
MMMU-Pro (Vals)Vals AI88.3%–
MortgageTaxVals AI68.1%–
SAGEVals AI49.9%–
Blueprint-Bench 2Epoch AI Benchmarking Hub33.6%†–
Long context
AA-LCRArtificial Analysis73.3%86.3%
Arena DocumentArena (LMArena)1453–
MLCRArtificial Analysis10.0%–
Composite
Epoch Capabilities IndexEpoch AI Benchmarking Hub154.9†–
LiveBench 2.0LiveBench–76.7%
LiveBench 1.0LiveBench74.6%–
AA Intelligence Index v4.3.2Artificial Analysis32.655.1
Vals Multimodal IndexVals AI62.9%–
AA Cyber IndexArtificial Analysis–64.1

Data as of 2026-10-24. Best configuration of each model; every score links to its source on the model pages.

What changed

  • Kimi K3.1 Pro: BenchLeader Index 65.6 → 66.8.
  • Kimi K3.1 Pro: 5 new results (FrontierCode 1.1 (AA), AA Cyber Index, CWE-Bench (AA)…).
  • Gemini 3.5 Flash (high): 1 new result (Harvey's Legal Agent Benchmark v1).
  • Kimi K3.1 Pro: first results.
  • Gemini 3.5 Flash (high): 1 score revision.
  • 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).
  • Gemini 3.5 Flash (high): 1 score revision.
  • Gemini 3.5 Flash (high): 2 score revisions.
  • Gemini 3.5 Flash (high): BenchLeader Index 63.0 → 62.5.

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

Gemini 3.5 Flash vs Kimi K3.1 Pro: questions

Is Gemini 3.5 Flash better than Kimi K3.1 Pro?
Gemini 3.5 Flash (high) and Kimi K3.1 Pro are neck and neck on quality (63.1 vs 66.8, within the ±6.8 margin). The BenchLeader Index combines every independent quality benchmark; the two are within the margin of error as of 2026-10-24, so check the category scores for your use.
Which is cheaper, Gemini 3.5 Flash or Kimi K3.1 Pro, and will that change?
Gemini 3.5 Flash is cheaper today: $3.38 against $4.00 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 Kimi K3.1 Pro for agents and tool use?
Kimi K3.1 Pro scores higher in agentic tasks (67 vs 63 on the category index, where 50 is average).
Which is better for long documents?
Kimi K3.1 Pro scores higher on long-context benchmarks (68 vs 62). Both accept 1,048,576 tokens of context.
Which has lower latency?
Gemini 3.5 Flash (high) answers first: 14.3 s against 27.7 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 Kimi K3.1 Pro?
Gemini 3.5 Flash streams faster: 222 against 81 output tokens per second.
Do independent benchmarks agree on Gemini 3.5 Flash vs Kimi K3.1 Pro?
Across the 12 benchmarks both have, Gemini 3.5 Flash leads 2, Kimi K3.1 Pro leads 10. Every overall index that rates both puts Kimi K3.1 Pro ahead.
When was Kimi K3.1 Pro released?
Kimi K3.1 Pro was released on 23 Oct 2026.