BenchLeader

Gemini 3.5 Flash vs GPT-6 Astra

Verdict
  • GPT-6 Astra (max) leads on quality: 70.6 vs 63.9.
  • Gemini 3.5 Flash (medium) is stronger in human preference, instruction following, long context, multimodal.
  • GPT-6 Astra (max) is stronger in agents & tools, coding, composite, knowledge, reasoning, maths.
  • Gemini 3.5 Flash (medium) is 6.5× cheaper ($3.38 vs $22.00 per 1M blended).
  • Gemini 3.5 Flash (medium) streams 3.9× faster (209 vs 54 tokens per second).
MetricGemini 3.5 Flash (medium)GPT-6 Astra (max)
BenchLeader Index63.970.6
Agents & tools score67.868.2
Coding score58.979.0
Composite score71.473.1
Human preference score67.4
Instruction following score72.2
Knowledge score73.979.8
Long context score63.6
Multimodal score67.6
Reasoning score66.870.9
Maths score77.0
Blended price $/M$3.38$22.00
Output speed209 tok/s54 tok/s
Time to first answer17.0 s328.6 s
Context window1M1.1M
GPQA Diamond95.8%
FrontierMath Tiers 1–393.7%
FrontierMath Tier 497.6%
OTIS Mock AIME100.0%
SimpleQA Verified75.6%
Terminal-Bench58.2%
SciCode56.5%
FrontierCode53.3%
LMArena Text1476
LMArena Hard Prompts1493
LMArena Coding1503
LMArena WebDev14911796
LMArena Vision1306
LMArena Agent12.5
LiveBench82.2%
LiveBench Reasoning92.7%
LiveBench Coding80.4%
LiveBench Agentic Coding57.3%
LiveBench Mathematics96.8%
LiveBench Data Analysis83.0%
LiveBench Language89.4%
AA Intelligence Index33.6
IFBench74.6%
AA-LCR74.3%
MMMU-Pro83.9%
AA-Omniscience20.8
Terminal-Bench Hard39.4%
GPQA Diamond (AA)92.1%
Humanity's Last Exam (AA)41.3%
τ²-Bench Telecom (AA)95.6%
Terminal-Bench 2.1 (Vals)87.3%
Vals Index66.6
ARC-AGI-197.5%
ARC-AGI-295.0%
ARC-AGI-362.7%

Data as of 2026-09-09. Best configuration of each model; every score links to its source on the model pages.