BenchLeader

Gemini 3.5 Flash vs Gemini 3.8 Flash

Full profiles: Gemini 3.5 Flash (Google) and Gemini 3.8 Flash (Google): every benchmark, price and rank.

Updated · Data from 10 sources

As of 24 Oct 2026, Gemini 3.5 Flash (high) and Gemini 3.8 Flash (high) are neck and neck on quality (63.1 vs 64.4 on the BenchLeader Index, inside the ±4.8 margin of error), and Gemini 3.8 Flash (high) costs 2.3× less, which makes it the better buy for most workloads. Gemini 3.8 Flash (high)'s current price runs until 31 Dec 2026; from 1 Jan 2027 both cost about $3.19 per 1M tokens blended, so then pick on use case: Gemini 3.5 Flash for agents & tools (63 vs 51), Gemini 3.8 Flash for reasoning (68 vs 61).

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
CodingGemini 3.8 Flash64 vs 60 category score; Arena WebDev 1585 vs 1499Medium
Agents & tool useGemini 3.5 Flash63 vs 51 category score; τ³-Banking (AA) 32.2% vs 45.0%High
MathsGemini 3.8 Flash62 vs 58 category score; FrontierMath Tiers 1–3 68.4% vs 62.8%Medium
ReasoningGemini 3.8 Flash68 vs 61 category score; GPQA Diamond 95.4% vs 92.8%Medium
KnowledgeGemini 3.8 Flash68 vs 65 category score; SimpleQA Verified 69.7% vs 66.2%Medium
Long documentsGemini 3.8 Flash66 vs 62 category score; AA-LCR 81.3% vs 73.3%Medium
Images and other mediaGemini 3.8 Flash68 vs 67 category score; Arena Vision 1315 vs 1308Medium
Chat quality (human preference)Gemini 3.8 Flash69 vs 67 on Arena votesMedium
Lowest costGemini 3.8 Flash (until 31 Dec 2026)$1.50 vs $3.38 per 1M blended; agentic coding session $0.060 vs $0.126; from 1 Jan 2027: $3.00 vs $3.38–
Fastest first answerGemini 3.5 Flash14.3 s (Gemini 3.5 Flash (high)) vs 25.1 s (Gemini 3.8 Flash (high)) 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 Gemini 3.8 Flash (high) are neck and neck on quality (63.1 vs 64.4, within the ±4.8 margin).
  • Gemini 3.5 Flash (high) is stronger in agents & tools, instruction following.
  • Gemini 3.8 Flash (high) is stronger in coding, composite, human preference, knowledge, long context, maths, multimodal, reasoning.
  • Gemini 3.8 Flash (high) is 2.3× cheaper ($1.50 vs $3.38 per 1M blended) until 31 Dec 2026, then $3.00 vs $3.38 from 1 Jan 2027.
  • Gemini 3.5 Flash (high) streams 1.6× faster (222 vs 141 tokens per second).

At a glance

SpecGemini 3.5 FlashGemini 3.8 Flash
DeveloperGoogleGoogle
Released19 May 20262 Sept 2026
Context window (tokens)1,048,5761,048,576
Compared atGemini 3.5 Flash (high)Gemini 3.8 Flash (high)
Open weightsNoNo
Price in / out / cached input per 1M$1.50 / $9.00 / $0.150$0.750 / $3.75 / $0.075
Announced price changeNone announced$1.50 / $7.50 from 1 Jan 2027

Limits, availability and announced prices from the vendors' own pages: ai.google.dev pricing (checked 20 Oct 2026). Everything else is from the day's data.

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)Gemini 3.8 Flash (high)Leader
Reasoning61.368.2Gemini 3.8 Flash
Coding59.963.5Gemini 3.8 Flash
Agents & tools63.450.9Gemini 3.5 Flash
Maths58.362.4Gemini 3.8 Flash
Knowledge65.268.4Gemini 3.8 Flash
Instruction following74.3–not comparable
Human preference66.869.1Gemini 3.8 Flash
Multimodal66.667.7Gemini 3.8 Flash
Long context61.665.7Gemini 3.8 Flash
Composite65.975.3Gemini 3.8 Flash

Where sources disagree

Across the 71 benchmarks both have, Gemini 3.5 Flash leads 6, Gemini 3.8 Flash leads 65. Every overall index that rates both puts Gemini 3.8 Flash ahead.

Overall indexGemini 3.5 Flash (high)Gemini 3.8 Flash (high)Leader
BenchLeader Index63.164.4neck and neck
AA Intelligence Index v4.3.232.640.9Gemini 3.8 Flash
Arena Text14771496Gemini 3.8 Flash

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)Gemini 3.8 Flash (high)
Blended price per 1M tokens, until 31 Dec 2026$3.38$1.50
Input / output per 1M$1.50 / $9.00$0.750 / $3.75
Blended price per 1M from 1 Jan 2027$3.38$3.00
Input / output per 1M from 1 Jan 2027$1.50 / $9.00$1.50 / $7.50
Cached input per 1M$0.150$0.075
Price per task: chat reply$0.0033$0.0014
Price per task: summarize a 30-page report$0.023$0.011
Price per task: code edit$0.022$0.010
Price per task: agentic coding session$0.126$0.060
Price per task: structured extraction$0.0048$0.0023
Cost to run a full benchmark suite$3.69$1.24
Output speed222 tok/s141 tok/s
Time to first answer14.3 s25.1 s
Time to a complete answer16.6 s28.7 s

Per token is not per task: on Artificial Analysis' full suite Gemini 3.5 Flash (high) cost $3.69 and Gemini 3.8 Flash (high) $1.24, because Gemini 3.5 Flash (high) used about 1.3× 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. Gemini 3.8 Flash (high) scores 64.4 and takes 25 s to its first answer token; Gemini 3.8 Flash (medium) scores 64.4 in 3 s, Gemini 3.8 Flash (low) scores 61.0 in 3 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

157 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)Gemini 3.8 Flash (high)
BenchLeader IndexBenchLeader63.164.4
Agents & tools scoreBenchLeader63.450.9
Coding scoreBenchLeader59.963.5
Composite scoreBenchLeader65.975.3
Human preference scoreBenchLeader66.869.1
Instruction following scoreBenchLeader74.3–
Knowledge scoreBenchLeader65.268.4
Long context scoreBenchLeader61.665.7
Maths scoreBenchLeader58.362.4
Multimodal scoreBenchLeader66.667.7
Reasoning scoreBenchLeader61.368.2
Blended price $/MBenchLeader$3.38$1.50
Output speedBenchLeader222 tok/s141 tok/s
Time to first answerBenchLeader14.3 s25.1 s
Context windowBenchLeader1,048,576 tokens1,048,576 tokens
Reasoning
GPQA DiamondEpoch AI Benchmarking Hub92.8%95.4%
Humanity's Last ExamScale AI / CAIS–44.5%†
SimpleBenchSimpleBench76.7%†–
Arena Hard PromptsArena (LMArena)14951517
LiveBench 2.0 ReasoningLiveBench–89.3%†
LiveBench 1.0 ReasoningLiveBench82.0%89.3%
GPQA Diamond (AA)Artificial Analysis92.2%95.3%
Humanity's Last Exam (AA)Artificial Analysis42.7%47.8%
GPQA Diamond (Vals)Vals AI92.7%94.4%
EnigmaEvalScale AI SEAL25.4%–
ARC-AGI-1ARC Prize92.5%98.5%
ARC-AGI-2ARC Prize72.1%89.2%
ARC-AGI-3ARC Prize–35.0%
CritPtArtificial Analysis13.1%18.3%
MysteryMechanismVals AI–36.5%
Chess PuzzlesEpoch AI Benchmarking Hub45.0%58.0%
Mystery Game PuzzlesEpoch AI Benchmarking Hub32.0%47.0%
LMCAEpoch AI Benchmarking Hub47.1%51.5%†
DTBenchEpoch AI Benchmarking Hub94.7%95.7%†
ForecastBenchForecastBench64.3%†–
Coding
SWE-bench Verified (Epoch)Epoch AI Benchmarking Hub79.3%–
SciCodeSciCode53.9%56.6%
WeirdMLWeirdML62.6%84.8%
FrontierCodeCognition–41.2%†
Arena CodingArena (LMArena)15081528
Show all 157 benchmarks
MetricPublisherGemini 3.5 Flash (high)Gemini 3.8 Flash (high)
Coding
Arena WebDevArena (LMArena)14991585
LiveBench 2.0 CodingLiveBench–82.2%†
LiveBench 1.0 CodingLiveBench78.2%72.5%
LiveCodeBenchVals AI87.6%89.5%
IOIVals AI–56.9%
SWE-bench (Vals)Vals AI78.8%80.0%
Code MigrationVals AI26.8%36.5%
Code Migration v1.1Vals AI–38.6%
ProgramBenchVals AI0.0%1.0%
SWE-bench MultimodalVals AI–40.8%
Vibe Code Bench 1-100Vals AI–18.8%
Vibe Code Bench v1.1Vals AI48.7%78.7%
SWE Atlas: Codebase QnAScale AI SEAL–47.0%†
SWE Atlas: RefactoringScale AI SEAL–44.8%†
SWE Atlas: Test WritingScale AI SEAL–53.7%†
Surface Evolver BenchEpoch AI Benchmarking Hub58.1%†76.9%
DeepSWE v1.1Epoch AI Benchmarking Hub36.1%73.8%
CursorBenchCursor–39.6%
ALE-BenchEpoch AI Benchmarking Hub911.01269.7
FrontierSWEEpoch AI Benchmarking Hub–19.6%
Terminal-Bench 4.0 (AA)Artificial Analysis6.6%19.7%
Terminal-Bench 2.1 (AA)Artificial Analysis78.7%87.6%
Startrise FrontendStartrise–64.6%†
FrontierCode 1.1 (AA)Artificial Analysis–36.4%
Agents & tools
Terminal-BenchTerminal-Bench–19.1%
Remote Labor IndexScale AI / CAIS–5.8%†
APEX-AgentsMercor27.5%†64.3%†
Arena AgentArena (LMArena)–3.6
LiveBench Long AgenticLiveBench–30.1%†
LiveBench BrowserLiveBench–64.0%†
LiveBench Agentic CodingLiveBench49.0%54.2%
Terminal-Bench HardArtificial Analysis40.9%–
τ²-Bench Telecom (AA)Artificial Analysis95.3%–
Terminal-Bench 2.1 (Vals)Vals AI74.2%81.3%
MCP AtlasScale AI SEAL83.6%–
HiL-BenchScale AI SEAL27.7%†41.5%†
GDPval-AA v2.1Artificial Analysis–46.8%
τ³-Banking (AA)Artificial Analysis32.2%45.0%
ITBench SRE (AA)Artificial Analysis40.4%52.5%
Analyst Agent (AA)Artificial Analysis45.0%46.3%
APEX-Agents (AA)Artificial Analysis47.0%–
CUA-benchVals AI–4.2%
CyberBenchVals AI–43.8%
Finance Agent v2Vals AI57.9%61.4%
Finance Agent v2.1Vals AI–65.8%
Harvey's Legal Agent Benchmark v1.1Vals AI–12.1%
Harvey's Legal Agent Benchmark v1Vals AI2.5%10.0%
Legal Research BenchVals AI30.8%38.9%
SkillsBenchVals AI52.7%58.0%
SREBenchVals AI–11.1%
Tax Agent BenchVals AI21.6%32.1%
Terminal-Bench 2.0 (Vals)Vals AI67.4%–
Terminal-Bench 4.0 (Vals)Vals AI6.1%19.7%
Terminal-Bench ScienceVals AI5.7%8.6%
Time Horizon Index: KSPVals AI–18.8%
Web Search IndexVals AI37.0%–
GBAEvalEpoch AI Benchmarking Hub6.7%†–
Vending-Bench 2Andon Labs5396.4†5093.8†
AutomationBenchArtificial Analysis42.1%59.9%
GDP.pdf (AA)Artificial Analysis19.8%21.0%
Harvey LAB-AA v1.1Harvey–0.0%
EnterpriseOps-GymArtificial Analysis50.1%–
AA-Briefcase v1.1Artificial Analysis8741202
Terminal-Bench-Science 0.1 (AA)Artificial Analysis–10.0%
CWE-Bench (AA)Artificial Analysis–52.5%
DeepSec-Bench (AA)Artificial Analysis–14.5%
CyberGym end-to-end (AA)Artificial Analysis–8.4%
FACTS SearchGoogle64.3%†76.3%†
Maths
FrontierMath Tiers 1–3Epoch AI Benchmarking Hub62.8%68.4%
FrontierMath Tier 4Epoch AI Benchmarking Hub26.8%21.9%
OTIS Mock AIMEEpoch AI Benchmarking Hub95.6%98.9%
ProofBenchVals AI31.0%48.0%†
LiveBench MathematicsLiveBench88.2%91.6%
AIME 2026MathArena95.0%†–
HMMT February 2026MathArena95.5%†–
MathArena ApexMathArena32.3%†–
Arena MathsArena (LMArena)14971526
Knowledge
SimpleQA VerifiedEpoch AI Benchmarking Hub66.2%69.7%
LiveBench 2.0 Data AnalysisLiveBench–54.0%†
LiveBench ResearchLiveBench–79.1%†
LiveBench 1.0 Data AnalysisLiveBench64.9%54.0%
AA-OmniscienceArtificial Analysis21.229.6
MMLU-ProVals AI89.5%90.2%
LegalBenchVals AI83.6%87.0%
CorpFinVals AI64.7%–
TaxEvalVals AI74.4%74.5%
PRBench FinanceScale AI SEAL–49.5%†
PRBench LegalScale AI SEAL–48.9%†
BioMysteryBenchVals AI–62.2%
Excel Modeling BenchmarkVals AI63.5%72.2%
Excel Modeling Benchmark v1.1Vals AI–72.9%
MedCodeVals AI55.8%48.1%
MedScribeVals AI76.6%84.5%
Public Benefits Bench v1.1Vals AI59.5%65.3%
DrugDiscoveryBenchScale AI SEAL50.0%–
EBR-benchEpoch AI Benchmarking Hub4.8%–
GDP.pdfEpoch AI Benchmarking Hub14.0%†23.2%
AA-Omniscience: accuracyArtificial Analysis51.4%54.6%
AA-Omniscience: non-hallucinationArtificial Analysis37.8%44.8%
Instruction following
LiveBench LanguageLiveBench84.6%87.8%
LiveBench Instruction FollowingLiveBench75.6%81.4%
IFBenchArtificial Analysis76.3%–
Arena Instruction FollowingArena (LMArena)14651490
Human preference
Arena TextArena (LMArena)14771496
EQ-Bench 4EQ-Bench1087†–
Arena Creative WritingArena (LMArena)14641485
Arena Multi-turnArena (LMArena)14801504
Arena Longer QueriesArena (LMArena)14821510
Multimodal
Arena VisionArena (LMArena)13081315
LiveBench DesignLiveBench–72.7%†
MMMU-ProArtificial Analysis84.3%85.6%
MMMU-Pro (Vals)Vals AI88.3%89.1%
MortgageTaxVals AI68.1%65.3%
SAGEVals AI49.9%35.1%
AudioMCScale AI SEAL–60.4%
AudioMC (text output)Scale AI SEAL–60.4%
Blueprint-Bench 2Epoch AI Benchmarking Hub33.6%†38.6%†
AA-3DArtificial Analysis–969
Long context
AA-LCRArtificial Analysis73.3%81.3%
Arena DocumentArena (LMArena)1453–
MLCRArtificial Analysis10.0%10.6%
Composite
Epoch Capabilities IndexEpoch AI Benchmarking Hub154.9†157.4†
LiveBench 2.0LiveBench–67.3%†
LiveBench 1.0LiveBench74.6%75.8%
AA Intelligence Index v4.3.2Artificial Analysis32.640.9
Vals IndexVals AI–56.0
Vals Finance IndexVals AI–60.5%
Vals RSI IndexVals AI–19.9%
Vals Science IndexVals AI–35.8%
Vals Multimodal IndexVals AI62.9%–
Vals Router IndexVals AI–56.0%†
AA Cyber IndexArtificial Analysis–25.1

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

What changed

  • Gemini 3.8 Flash: list price moves to $1.50 / $7.50 per 1M input / output tokens (announced).
  • Gemini 3.5 Flash (high): 1 new result (Harvey's Legal Agent Benchmark v1).
  • Gemini 3.8 Flash (high): 8 new results (Code Migration v1.1, Excel Modeling Benchmark v1.1, Finance Agent v2.1…).
  • Gemini 3.5 Flash (high): 1 score revision.
  • Gemini 3.8 Flash (high): 1 score revision.
  • Gemini 3.8 Flash (high): 3 score revisions.
  • Gemini 3.5 Flash (high): BenchLeader Index 62.5 → 63.2.
  • Gemini 3.8 Flash (high): BenchLeader Index 63.7 → 64.5.
  • Gemini 3.5 Flash (high): 3 new results (GDPval-AA v2.1, AA-Omniscience: accuracy, AA-Omniscience: non-hallucination).
  • Gemini 3.8 Flash (high): 1 new result (AudioMC (text output)).

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

Gemini 3.5 Flash vs Gemini 3.8 Flash: questions

Is Gemini 3.5 Flash better than Gemini 3.8 Flash?
Gemini 3.5 Flash (high) and Gemini 3.8 Flash (high) are neck and neck on quality (63.1 vs 64.4, within the ±4.8 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 Gemini 3.8 Flash, and will that change?
Gemini 3.8 Flash is cheaper today: $1.50 against $3.38 per million tokens, blended at three input tokens per output token. Yes, that changes: Gemini 3.8 Flash's list price changes on 1 Jan 2027, and from then they cost about the same ($3.38 vs $3.00 blended).
Is Gemini 3.5 Flash better than Gemini 3.8 Flash for coding?
Gemini 3.8 Flash scores higher in coding (64 vs 60 on the category index, where 50 is average). On Arena WebDev, the top shared coding benchmark, it is 1499 for Gemini 3.5 Flash against 1585 for Gemini 3.8 Flash.
Is Gemini 3.5 Flash better than Gemini 3.8 Flash for agents and tool use?
Gemini 3.5 Flash scores higher in agentic tasks (63 vs 51 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 45.0% for Gemini 3.8 Flash.
Which is better for long documents?
Gemini 3.8 Flash scores higher on long-context benchmarks (66 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 25.1 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 Gemini 3.8 Flash?
Gemini 3.5 Flash streams faster: 222 against 141 output tokens per second.
Do independent benchmarks agree on Gemini 3.5 Flash vs Gemini 3.8 Flash?
Across the 71 benchmarks both have, Gemini 3.5 Flash leads 6, Gemini 3.8 Flash leads 65. Every overall index that rates both puts Gemini 3.8 Flash ahead.
When was Gemini 3.8 Flash released?
Gemini 3.8 Flash was released on 2 Sept 2026.