Enter opens the highlighted result. Esc closes.

Claude Sonnet 5.5 vs Gemini 3.6 Flash

Claude Sonnet 5.5 leads Gemini 3.6 Flash on coding, 87.3 to 62.5 on the Vibe Coding Index, and Gemini 3.6 Flash costs 2.7x less per output token ($3.75 vs $10.00 per million). Updated October 21, 2026; 79 benchmarks have a result for both.

Replace Claude Sonnet 5.5 Replace Gemini 3.6 Flash
Claude Sonnet 5.5Anthropic
Coding
87.3
Overall
82.8
Output $/M
$10.00
64
Gemini 3.6 FlashGoogle
Coding
62.5
Overall
68.3
Output $/M
$3.75
15
vs boards won of 79 shared

Claude Sonnet 5.5 or Gemini 3.6 Flash: which to pick

Pick Claude Sonnet 5.5 for coding: it scores 87.3 on the Vibe Coding Index against 62.5 for Gemini 3.6 Flash.

Pick Gemini 3.6 Flash for output tokens 2.7x cheaper ($3.75 vs $10.00 per million) and a larger context window (1.05M against 1M tokens).

Model AClaude Sonnet 5.5Anthropic87.3/1005 independent benchmarksNo cost per solved taskModel BGemini 3.6 FlashGoogle62.5/1004 independent benchmarks$1.49 per solved task
Shared results
79
Claude Sonnet 5.5 only
17
Gemini 3.6 Flash only
30
Like-for-like categories
8 of 9

Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.

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.

At a glance

Coding index
Claude Sonnet 5.5 87.3 from 5 benchmarks, Gemini 3.6 Flash 62.5 from 4 benchmarks.
Widest category
Math, 27.2 points apart on average over 6 shared benchmarks.
Widest single gap
ProofBench: Claude Sonnet 5.5 100.0% against Gemini 3.6 Flash 36.0%, 64.0 points apart on a 0 to 100 scale.
Output price
Claude Sonnet 5.5 $10.00 against Gemini 3.6 Flash $3.75 per million output tokens, 2.7x apart.
Context window
Claude Sonnet 5.5 takes 1M tokens, Gemini 3.6 Flash 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.

Boards won, where both have a result
CategoryClaude Sonnet 5.5BarsGemini 3.6 FlashTies
Coding160
Intelligence20
Agentic work100
Reasoning90
Math51
Knowledge24
Web design60
General1410
All shared boards6415
CodingLike-for-likeSix of these boards feed the Vibe Coding Index160
Coding benchmarks for Claude Sonnet 5.5 and Gemini 3.6 Flash
BenchmarkClaude Sonnet 5.5Gemini 3.6 FlashLeader
LiveBench coding94.7%Not measuredOnly Claude Sonnet 5.5 measured
LMArena WebDev17681538Claude Sonnet 5.5
AA Coding IndexNot measured69.2Only Gemini 3.6 Flash measured
LiveCodeBench (Vals AI)Not measured88.1%Only Gemini 3.6 Flash measured
SWE-bench Verified (Vals AI)Not measured79.6%Only Gemini 3.6 Flash measured
Terminal-Bench 4 (Vals AI)64.1%Not measuredOnly Claude Sonnet 5.5 measured
Vibe Code Bench (Vals AI)92.4%64.0%Claude Sonnet 5.5
Code migration (Vals AI)69.8%30.9%Claude Sonnet 5.5
ProgramBench (Vals AI)6.5%0.0%Claude Sonnet 5.5
IOI (Vals AI)83.1%35.1%Claude Sonnet 5.5
Terminal-Bench 2.1 (Vals AI)83.2%73.8%Claude Sonnet 5.5
SWE-bench Multimodal (Vals AI)58.3%Not measuredOnly Claude Sonnet 5.5 measured
CyberBench (Vals AI)59.6%45.4%Claude Sonnet 5.5
SciCode61.0%53.4%Claude Sonnet 5.5
FrontierCode52.1%34.4%Claude Sonnet 5.5
FrontierSWE61.9%Not measuredOnly Claude Sonnet 5.5 measured
WeirdMLNot measured56.1%Only Gemini 3.6 Flash measured
ALE-Bench1819.1715.5Claude Sonnet 5.5
LMArena Text: coding15131491Claude Sonnet 5.5
LMArena Text: software and IT15041492Claude Sonnet 5.5
LMArena WebDev: React18171528Claude Sonnet 5.5
LMArena WebDev: HTML17411547Claude Sonnet 5.5
LMArena WebDev: from an image17371545Claude Sonnet 5.5
SciCode13.8%10.8%Claude Sonnet 5.5
Neither model has a result on the other 15 boards here
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index20
Intelligence benchmarks for Claude Sonnet 5.5 and Gemini 3.6 Flash
BenchmarkClaude Sonnet 5.5Gemini 3.6 FlashLeader
AA Intelligence Index56.034.0Claude Sonnet 5.5
Epoch Capabilities Index166.2154.5Claude Sonnet 5.5
Agentic workLike-for-likePublic boards, shown as published, kept out of the index100
Agentic work benchmarks for Claude Sonnet 5.5 and Gemini 3.6 Flash
BenchmarkClaude Sonnet 5.5Gemini 3.6 FlashLeader
AA Agentic IndexNot measured29.0Only Gemini 3.6 Flash measured
Design Arena: agents building web apps13061197Claude Sonnet 5.5
Design Arena: agents building full-stack appsNot measured1181Only Gemini 3.6 Flash measured
Design Arena: agents building mobile apps12571199Claude Sonnet 5.5
Design Arena: agents building Android appsNot measured1203Only Gemini 3.6 Flash measured
Design Arena: agents building gamesNot measured1181Only Gemini 3.6 Flash measured
Design Arena: HTML slidesNot measured1148Only Gemini 3.6 Flash measured
Design Arena: PowerPoint slidesNot measured1146Only Gemini 3.6 Flash measured
Design Arena: spreadsheets12441034Claude Sonnet 5.5
LiveBench research83.6%Not measuredOnly Claude Sonnet 5.5 measured
LiveBench browser84.0%Not measuredOnly Claude Sonnet 5.5 measured
LiveBench long agentic78.8%Not measuredOnly Claude Sonnet 5.5 measured
SREBench (Vals AI)30.1%Not measuredOnly Claude Sonnet 5.5 measured
Finance Agent (Vals AI)58.1%56.3%Claude Sonnet 5.5
Tax Agent Bench (Vals AI)42.0%18.0%Claude Sonnet 5.5
Legal Research Bench (Vals AI)48.1%25.0%Claude Sonnet 5.5
Harvey's Legal Agent Benchmark (Vals AI)10.4%Not measuredOnly Claude Sonnet 5.5 measured
Excel Modeling Benchmark (Vals AI)75.7%65.4%Claude Sonnet 5.5
BioMysteryBench (Vals AI)81.1%58.5%Claude Sonnet 5.5
Terminal-Bench-Science (Vals AI)47.1%4.3%Claude Sonnet 5.5
Vals Science Index59.1%Not measuredOnly Claude Sonnet 5.5 measured
APEX-Agents75.5%46.9%Claude Sonnet 5.5
SpireClimb1.3%Not measuredOnly Claude Sonnet 5.5 measured
Vending-Bench 2$11,165Not measuredOnly Claude Sonnet 5.5 measured
Neither model has a result on the other 17 boards here
ReasoningLike-for-likePublic boards, shown as published, kept out of the index90
Reasoning benchmarks for Claude Sonnet 5.5 and Gemini 3.6 Flash
BenchmarkClaude Sonnet 5.5Gemini 3.6 FlashLeader
GPQA DiamondNot measured93.4%Only Gemini 3.6 Flash measured
LiveBench reasoning91.6%Not measuredOnly Claude Sonnet 5.5 measured
MysteryMechanism (Vals AI)49.1%Not measuredOnly Claude Sonnet 5.5 measured
MMMU Pro (Vals AI)Not measured88.4%Only Gemini 3.6 Flash measured
GPQA Diamond (Artificial Analysis run)Not measured92.8%Only Gemini 3.6 Flash measured
Humanity's Last Exam (Artificial Analysis run)55.0%40.8%Claude Sonnet 5.5
GPQA Diamond (Epoch AI run)95.6%94.1%Claude Sonnet 5.5
ARC-AGINot measured91.2%Only Gemini 3.6 Flash measured
ARC-AGI-2Not measured60.4%Only Gemini 3.6 Flash measured
Chess puzzles59.0%42.0%Claude Sonnet 5.5
Mystery game puzzles65.0%30.0%Claude Sonnet 5.5
LMArena Text: hard prompts14941486Claude Sonnet 5.5
LMArena Text: expert15311490Claude Sonnet 5.5
LMArena Text: hard prompts in English15021484Claude Sonnet 5.5
LMArena Vision: diagrams13291314Claude Sonnet 5.5
LMArena Vision: homework13311314Claude Sonnet 5.5
Neither model has a result on the other 6 boards here
MathLike-for-likePublic boards, shown as published, kept out of the index51
Math benchmarks for Claude Sonnet 5.5 and Gemini 3.6 Flash
BenchmarkClaude Sonnet 5.5Gemini 3.6 FlashLeader
OTIS Mock AIME100.0%94.2%Claude Sonnet 5.5
FrontierMath, tiers 1 to 388.8%58.9%Claude Sonnet 5.5
FrontierMath, tier 480.5%22.0%Claude Sonnet 5.5
ProofBench100.0%36.0%Claude Sonnet 5.5
LMArena Text: math14971508Gemini 3.6 Flash
LMArena Text: mathematical work15101492Claude Sonnet 5.5
Neither model has a result on the other 7 boards here
KnowledgeLike-for-likePublic boards, shown as published, kept out of the index24
Knowledge benchmarks for Claude Sonnet 5.5 and Gemini 3.6 Flash
BenchmarkClaude Sonnet 5.5Gemini 3.6 FlashLeader
MMLU ProNot measured89.3%Only Gemini 3.6 Flash measured
LegalBench (Vals AI)Not measured86.7%Only Gemini 3.6 Flash measured
CorpFin (Vals AI)Not measured63.3%Only Gemini 3.6 Flash measured
TaxEval (Vals AI)Not measured74.9%Only Gemini 3.6 Flash measured
MortgageTax (Vals AI)Not measured67.6%Only Gemini 3.6 Flash measured
MedCode (Vals AI)52.9%53.1%Gemini 3.6 Flash
SimpleQA Verified46.5%66.2%Gemini 3.6 Flash
LMArena Text: science14831489Gemini 3.6 Flash
LMArena Text: medicine and healthcare14641469Gemini 3.6 Flash
LMArena Text: legal and government14831479Claude Sonnet 5.5
LMArena Text: business and finance14681464Claude Sonnet 5.5
FACTS Benchmark SuiteNot measured65.3%Only Gemini 3.6 Flash measured
Neither model has a result on the other 6 boards here
Web designLike-for-likePublic boards, shown as published, kept out of the index60
Web design benchmarks for Claude Sonnet 5.5 and Gemini 3.6 Flash
BenchmarkClaude Sonnet 5.5Gemini 3.6 FlashLeader
Design Arena: websites13261300Claude Sonnet 5.5
Design Arena: UI components13651297Claude Sonnet 5.5
Design Arena: game dev14691263Claude Sonnet 5.5
Design Arena: data viz13941289Claude Sonnet 5.5
Design Arena: 3D14521272Claude Sonnet 5.5
Design Arena: all code categories13641290Claude Sonnet 5.5
Design Arena: ASCII artNot measured1281Only Gemini 3.6 Flash measured
LiveBench design85.0%Not measuredOnly Claude Sonnet 5.5 measured
Neither model has a result on the other 1 board here
GeneralLike-for-likePublic boards, shown as published, kept out of the index1410
General benchmarks for Claude Sonnet 5.5 and Gemini 3.6 Flash
BenchmarkClaude Sonnet 5.5Gemini 3.6 FlashLeader
Vals Index70.8%Not measuredOnly Claude Sonnet 5.5 measured
LiveBench data analysis59.5%Not measuredOnly Claude Sonnet 5.5 measured
Public Benefits Bench (Vals AI)67.2%56.6%Claude Sonnet 5.5
SAGE (Vals AI)51.8%48.7%Claude Sonnet 5.5
MedScribe (Vals AI)91.1%79.7%Claude Sonnet 5.5
Vals Multimodal IndexNot measured65.1%Only Gemini 3.6 Flash measured
Long context reasoning (AA-LCR)82.7%80.0%Claude Sonnet 5.5
DTBench97.3%95.5%Claude Sonnet 5.5
LMCA68.3%44.9%Claude Sonnet 5.5
Furniture assembly75.0%23.3%Claude Sonnet 5.5
LMArena Text14731480Gemini 3.6 Flash
LMArena Text: instruction following14921467Claude Sonnet 5.5
LMArena Text: creative writing14671466Claude Sonnet 5.5
LMArena Vision12871299Gemini 3.6 Flash
LMArena Text: English14841482Claude Sonnet 5.5
LMArena Text: non-English14561470Gemini 3.6 Flash
LMArena Text: Chinese15351531Claude Sonnet 5.5
LMArena Text: GermanNot measured1480Only Gemini 3.6 Flash measured
LMArena Text: JapaneseNot measured1475Only Gemini 3.6 Flash measured
LMArena Text: KoreanNot measured1429Only Gemini 3.6 Flash measured
LMArena Text: French14991503Gemini 3.6 Flash
LMArena Text: Spanish14511476Gemini 3.6 Flash
LMArena Text: Russian14541488Gemini 3.6 Flash
LMArena Text: PolishNot measured1473Only Gemini 3.6 Flash measured
LMArena Text: multi-turn14651481Gemini 3.6 Flash
LMArena Text: longer queries14951475Claude Sonnet 5.5
LMArena Text: writing and language14741470Claude Sonnet 5.5
LMArena Text: entertainment and media14611456Claude Sonnet 5.5
LMArena Vision: English12891295Gemini 3.6 Flash
LMArena Vision: ChineseNot measured1357Only Gemini 3.6 Flash measured
LMArena Vision: reading text12971312Gemini 3.6 Flash
LMArena Vision: humorNot measured1289Only Gemini 3.6 Flash measured
LMArena Vision: creative writing12421278Gemini 3.6 Flash
LMArena DocumentNot measured1456Only Gemini 3.6 Flash measured
Neither model has a result on the other 12 boards here
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
Image generation benchmarks for Claude Sonnet 5.5 and Gemini 3.6 Flash
BenchmarkClaude Sonnet 5.5Gemini 3.6 FlashLeader
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

Claude Sonnet 5.5$0.0070Fits in one request
Gemini 3.6 Flash$0.0026Fits in one request

Gemini 3.6 Flash costs less

Repository review

50K input + 3K output tokens

Claude Sonnet 5.5$0.130Fits in one request
Gemini 3.6 Flash$0.049Fits in one request

Gemini 3.6 Flash costs less

Agent loop

200K input + 10K output tokens

Claude Sonnet 5.5$0.500Fits in one request
Gemini 3.6 Flash$0.188Fits in one request

Gemini 3.6 Flash 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.

Specifications of Claude Sonnet 5.5 and Gemini 3.6 Flash
SpecificationAnthropic Claude Sonnet 5.5Google Gemini 3.6 Flash
MakerAnthropicGoogle
WeightsNo public weights listedNo public weights listed
ReleasedSeptember 28, 2026July 21, 2026
Context window1M1.05M
Input $/Mtok$2.00$0.75
Output $/Mtok$10.00$3.75
Coding index87.362.5
Independent measurements behind it54
Cost per solved taskNot computable$1.49
SourceOpenRouter listingOpenRouter listing

Questions

Is Claude Sonnet 5.5 better than Gemini 3.6 Flash for coding?

Pick Claude Sonnet 5.5 for coding: it scores 87.3 on the Vibe Coding Index against 62.5 for Gemini 3.6 Flash. Pick Gemini 3.6 Flash for output tokens 2.7x cheaper ($3.75 vs $10.00 per million) and a larger context window (1.05M against 1M tokens).

Which is cheaper, Claude Sonnet 5.5 or Gemini 3.6 Flash?

Claude Sonnet 5.5 costs $2.00 per million input tokens and $10.00 per million output tokens; Gemini 3.6 Flash costs $0.75 and $3.75. Cost per solved task is known for Gemini 3.6 Flash only.

Which has the bigger context window, Claude Sonnet 5.5 or Gemini 3.6 Flash?

Gemini 3.6 Flash, with 1.05M tokens against 1M.

How many benchmarks is the Claude Sonnet 5.5 vs Gemini 3.6 Flash comparison based on?

79 benchmarks have a result for both models as of October 21, 2026. Claude Sonnet 5.5's coding index rests on 5 independent benchmarks and Gemini 3.6 Flash's on 4. Where only one model has a result, the page says so instead of naming a winner.

Compare next

Embed this comparison on your site

Free under CC BY 4.0, while the source link stays visible. Preview the frame · Terms and other embeds

<iframe src="https://llmbenchmark.ai/embed/compare/claude-sonnet-5-5-vs-gemini-3-6-flash" title="Claude Sonnet 5.5 vs Gemini 3.6 Flash, LLMBenchmark.ai" width="100%" height="360" style="border:0;max-width:100%" loading="lazy"></iframe>
<p style="font:13px/1.4 sans-serif;margin:6px 0 0">Source: <a href="https://llmbenchmark.ai/compare/claude-sonnet-5-5-vs-gemini-3-6-flash">LLMBenchmark.ai, Claude Sonnet 5.5 vs Gemini 3.6 Flash</a></p>