Claude Opus 4.6 vs Gemini 3.5 Flash

  • Claude Opus 4.6 rates higher on LMArena’s text leaderboard: 1502 against 1482.
  • Gemini 3.5 Flash is cheaper: $1.50 / $9 per million input / output tokens, against $5 / $25 for Claude Opus 4.6.
  • On the 7 Vals AI benchmarks both have taken, Claude Opus 4.6 wins 1 and Gemini 3.5 Flash wins 6 (Claude Opus 4.6: Vibe Code Bench).
LMArena text rating over time
14701483149515081520Feb 26Apr 26Jun 26Aug 26Oct 26
LatestClaude Opus 4.6 1502Gemini 3.5 Flash 1482

Side by side

Models (2/6)
  • Claude Opus 4.6
  • Gemini 3.5 Flash
BenchmarkClaude Opus 4.6Gemini 3.5 Flash
The model
LabAnthropicGoogle
Released2026-02-042026-05-19
WeightsProprietaryProprietary
Context window1M1M
Input, per 1M tokens$5$1.50
Output, per 1M tokens$25$9
LMArena, people’s votes
LMArena TextMillions of people compare two anonymous models side by side and vote for the better answer1502#6 of 3511482#18 of 351
LMArena WebDevPeople ask two anonymous models to build the same web app, try both and vote for the better one1546#45 of 1241499#63 of 124
LMArena VisionSide-by-side votes on prompts that include an image1316#6 of 1461308#13 of 146
LMArena CodingLMArena’s text votes on prompts that ask for code1534#3 of 3461493#33 of 346
LMArena MathLMArena’s text votes on math prompts1518#7 of 3391504#12 of 339
LMArena Creative writingLMArena’s text votes on stories, poems and other creative writing1505#4 of 3491470#17 of 349
LMArena Hard promptsLMArena’s text votes on the hardest prompts1524#5 of 3511488#23 of 351
LMArena Instruction followingLMArena’s text votes on prompts with specific instructions to follow1521#3 of 3511467#33 of 351
Vals AI, coding
Terminal-Bench 4.0Frontier-difficulty tasks an agent completes in a real terminal—6.06%#45 of 55
SWE-benchReal GitHub issues from open-source projects78.20%#30 of 8578.80%#27 of 85
Vibe Code BenchBuilding complete web apps from a plain-language brief, graded on whether the app works53.50%#57 of 11548.68%#60 of 115
LiveCodeBenchFresh competitive programming problems, collected after models’ training cut-offs to avoid contamination84.68%#38 of 14387.60%#12 of 143
Vals AI, finance
Tax Agent BenchAgentic research into US corporate tax questions—21.65%#47 of 76
Vals AI, law
Legal Research BenchAgentic US legal research—30.77%#49 of 85
Vals AI, medicine
MedCodeAssigning the right medical billing codes from clinical notes48.24%#30 of 10755.83%#6 of 107
MedQAMedical licensing exam questions, measured on accuracy and on robustness to bias95.41%#12 of 92—
Vals AI, reasoning
GPQA DiamondGraduate-level questions in biology, physics and chemistry that experts answer well and search does not89.65%#29 of 13892.68%#14 of 138
MMLU-ProHarder, reasoning-focused multiple choice across 14 subjects, from law to engineering89.11%#15 of 13889.52%#10 of 138
AIMEProblems from the American Invitational Mathematics Examination, a qualifier for the US Math Olympiad95.63%#9 of 96—
MMMUCollege-level questions that need both an image and text83.87%#29 of 9388.27%#8 of 93
Terminal-Bench ScienceExpert-written scientific research workflows, run by an agent in a terminal—5.71%#21 of 42

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Questions

Which is better, Claude Opus 4.6 or Gemini 3.5 Flash?

Claude Opus 4.6 rates higher on LMArena’s text leaderboard: 1502 against 1482. Gemini 3.5 Flash is cheaper: $1.50 / $9 per million input / output tokens, against $5 / $25 for Claude Opus 4.6. On the 7 Vals AI benchmarks both have taken, Claude Opus 4.6 wins 1 and Gemini 3.5 Flash wins 6 (Claude Opus 4.6: Vibe Code Bench).

Which is cheaper, Claude Opus 4.6 or Gemini 3.5 Flash?

Gemini 3.5 Flash is cheaper: $1.50 / $9 per million input / output tokens, against $5 / $25 for Claude Opus 4.6.

Sources

Every number on this page comes from these sources; models without a published number show none. Download the data. Cite as “Nexus Explorer, nexus.inc/models”.