BenchLeader

GPT-5.2-Codex vs GPT-6 Astra

Verdict
  • GPT-6 Astra (max) leads on quality: 70.9 vs 60.8.
  • GPT-5.2-Codex is stronger in instruction following, long context, multimodal.
  • GPT-6 Astra (max) is stronger in agents & tools, coding, composite, knowledge, maths, reasoning.
  • GPT-5.2-Codex is 4.2× cheaper ($4.81 vs $20.00 per 1M blended).
MetricGPT-5.2-CodexGPT-6 Astra (max)
BenchLeader Index60.870.9
Agents & tools score63.568.2
Coding score55.778.6
Composite score56.872.9
Instruction following score75.1
Knowledge score63.180.0
Long context score67.8
Multimodal score60.7
Maths score77.2
Reasoning score73.6
Blended price $/M$4.81$20.00
Output speed25 tok/s27 tok/s
Time to first answer6.7 s337.3 s
Context window400k1.1M
GPQA Diamond95.8%
FrontierMath Tiers 1–393.7%
FrontierMath Tier 497.6%
OTIS Mock AIME100.0%
SimpleQA Verified75.6%
Terminal-Bench66.5%58.2%
SciCode56.5%
APEX-Agents27.6%
FrontierCode53.3%
LMArena WebDev13391796
LMArena Agent12.5
LiveBench74.0%82.2%
LiveBench Reasoning77.7%92.7%
LiveBench Coding83.6%80.4%
LiveBench Agentic Coding49.4%57.3%
LiveBench Mathematics88.8%96.8%
LiveBench Data Analysis78.2%83.0%
LiveBench Language73.7%89.4%
AA Intelligence Index28.5
IFBench77.6%
AA-LCR82.3%
MMMU-Pro76.3%
AA-Omniscience-2.2
Terminal-Bench Hard37.1%
GPQA Diamond (AA)89.9%
Humanity's Last Exam (AA)35.7%
τ²-Bench Telecom (AA)92.1%
LiveCodeBench88.0%
Terminal-Bench 2.1 (Vals)87.3%
Vals Index66.6
SWE-Bench Pro41.0%
SWE-bench Verified (bash only)72.8%
SWE-bench Verified (any scaffold)72.8%
ARC-AGI-197.5%
ARC-AGI-295.0%
ARC-AGI-398.6%

Data as of 2026-09-10. Best configuration of each model; every score links to its source on the model pages.

GPT-5.2-Codex vs GPT-6 Astra: questions

Is GPT-5.2-Codex better than GPT-6 Astra?
GPT-6 Astra (max) leads on quality: 70.9 vs 60.8. The BenchLeader Index combines every independent quality benchmark; GPT-6 Astra (max) is ahead overall as of 2026-09-10, but check the category scores for your use.
Is GPT-5.2-Codex better than GPT-6 Astra for coding?
GPT-6 Astra scores higher in coding (79 vs 56 on the category index, where 50 is average).
Is GPT-5.2-Codex better than GPT-6 Astra for agentic tasks?
GPT-6 Astra scores higher in agentic tasks (68 vs 64 on the category index, where 50 is average).
Which is cheaper, GPT-5.2-Codex or GPT-6 Astra?
GPT-5.2-Codex is cheaper: $4.81 against $20.00 per million tokens, blended at three input tokens per output token.
Which is faster, GPT-5.2-Codex or GPT-6 Astra?
GPT-6 Astra streams faster: 27 against 25 output tokens per second.
Which has the larger context window?
GPT-6 Astra accepts more context: 1.1M against 400k tokens.