BenchLeader

Claude Sonnet 5.5 vs Gemini 3 Flash

Verdict
  • Claude Sonnet 5.5 (max) leads on quality: 67.6 vs 59.2.
  • Claude Sonnet 5.5 (max) is stronger in agents & tools, coding, composite, long context, maths, reasoning.
  • Gemini 3 Flash (thinking) is stronger in knowledge, instruction following, multimodal.
  • Gemini 3 Flash (thinking) is 3.6× cheaper ($1.13 vs $4.00 per 1M blended).
  • Gemini 3 Flash (thinking) streams 1.5× faster (208 vs 141 tokens per second).
MetricClaude Sonnet 5.5 (max)Gemini 3 Flash (thinking)
BenchLeader Index67.659.2
Agents & tools score69.555.2
Coding score69.8–
Composite score72.659.3
Knowledge score65.466.2
Long context score66.664.2
Maths score72.9–
Reasoning score81.155.4
Instruction following score–75.6
Multimodal score–63.1
Blended price $/M$4.00$1.13
Output speed141 tok/s208 tok/s
Time to first answer487.1 s5.8 s
Context window1M1.0M
GPQA Diamond95.6%–
FrontierMath Tiers 1–388.8%–
FrontierMath Tier 480.5%–
OTIS Mock AIME100.0%–
SimpleQA Verified46.5%–
Terminal-Bench61.8%–
SciCode61.0%–
APEX-Agents75.5%–
ProofBench100.0%–
LMArena Agent12–
LiveBench75.7%–
LiveBench Reasoning91.6%–
LiveBench Coding91.4%–
LiveBench Agentic Coding56.3%–
LiveBench Mathematics96.1%–
LiveBench Data Analysis59.5%–
LiveBench Language78.0%–
LiveBench Instruction Following56.8%–
AA Intelligence Index v4.3.25626.3
IFBench–78.0%
AA-LCR82.7%78.0%
MMMU-Pro–79.9%
AA-Omniscience32.310.1
Terminal-Bench Hard–38.6%
GPQA Diamond (AA)–89.8%
Humanity's Last Exam (AA)55.0%36.6%
SciCode (AA)61.0%–
τ²-Bench Telecom (AA)–80.4%
CritPt31.4%8.6%
GDPval-AA v2.167.0%–
τ³-Banking (AA)–20.8%
Analyst Agent (AA)57.5%–
APEX-Agents (AA)–27.7%
Mystery Game Puzzles65.0%–
CursorBench55.5%–
FrontierSWE61.9%–
Terminal-Bench 4.0 (AA)63.6%–
AutomationBench71.8%–
GDP.pdf25.8%–
MLCR75.0%–
Harvey LAB2.8%–
AA-Omniscience: accuracy54.0%53.4%
AA-Omniscience: non-hallucination53.0%7.0%
AA-Briefcase v1.11823–

Data as of 2026-10-11. Best configuration of each model; every score links to its source on the model pages.

Claude Sonnet 5.5 vs Gemini 3 Flash: questions

Is Claude Sonnet 5.5 better than Gemini 3 Flash?
Claude Sonnet 5.5 (max) leads on quality: 67.6 vs 59.2. The BenchLeader Index combines every independent quality benchmark; Claude Sonnet 5.5 (max) is ahead overall as of 2026-10-11, but check the category scores for your use.
Is Claude Sonnet 5.5 better than Gemini 3 Flash for agentic tasks?
Claude Sonnet 5.5 scores higher in agentic tasks (70 vs 55 on the category index, where 50 is average).
Which is cheaper, Claude Sonnet 5.5 or Gemini 3 Flash?
Gemini 3 Flash is cheaper: $1.13 against $4.00 per million tokens, blended at three input tokens per output token.
Which is faster, Claude Sonnet 5.5 or Gemini 3 Flash?
Gemini 3 Flash streams faster: 208 against 141 output tokens per second.
Which has the larger context window?
Gemini 3 Flash accepts more context: 1.0M against 1M tokens.