BenchLeader

GPT-5.2-Codex vs GPT-5.4

Verdict
  • GPT-5.4 leads on quality: 63.5 vs 60.8.
  • GPT-5.2-Codex is stronger in coding, instruction following, long context.
  • GPT-5.4 is stronger in agents & tools, composite, knowledge, multimodal, human preference, reasoning.
  • GPT-5.2-Codex is 1.2× cheaper ($4.81 vs $5.63 per 1M blended).
  • GPT-5.4 streams 5.2× faster (129 vs 25 tokens per second).
MetricGPT-5.2-CodexGPT-5.4
BenchLeader Index60.863.5
Agents & tools score63.566.2
Coding score55.751.6
Composite score56.878.3
Instruction following score75.171.9
Knowledge score63.166.9
Long context score67.867.6
Multimodal score60.764.0
Human preference score64.7
Reasoning score62.6
Blended price $/M$4.81$5.63
Output speed25 tok/s129 tok/s
Time to first answer6.7 s124.6 s
Context window400k1.1M
Terminal-Bench66.5%81.8%
APEX-Agents27.6%34.9%
Epoch Capabilities Index156.9
LMArena Text1466
LMArena Hard Prompts1488
LMArena Coding1514
LMArena WebDev13391386
LMArena Vision1293
LiveBench74.0%
LiveBench Reasoning77.7%
LiveBench Coding83.6%
LiveBench Agentic Coding49.4%
LiveBench Mathematics88.8%
LiveBench Data Analysis78.2%
LiveBench Language73.7%
AA Intelligence Index28.539.0
IFBench77.6%74.0%
AA-LCR82.3%82.0%
MMMU-Pro76.3%78.4%
AA-Omniscience-2.25.8
Terminal-Bench Hard37.1%57.6%
GPQA Diamond (AA)89.9%92.0%
Humanity's Last Exam (AA)35.7%43.7%
τ²-Bench Telecom (AA)92.1%87.1%
LiveCodeBench88.0%
SWE-Bench Pro41.0%
HiL-Bench9.7%
EQ-Bench 41272
Kagi LLM Benchmark63.8%
SWE-bench Verified (bash only)72.8%
SWE-bench Verified (any scaffold)72.8%

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-5.4: questions

Is GPT-5.2-Codex better than GPT-5.4?
GPT-5.4 leads on quality: 63.5 vs 60.8. The BenchLeader Index combines every independent quality benchmark; GPT-5.4 is ahead overall as of 2026-09-10, but check the category scores for your use.
Is GPT-5.2-Codex better than GPT-5.4 for coding?
GPT-5.2-Codex scores higher in coding (56 vs 52 on the category index, where 50 is average).
Is GPT-5.2-Codex better than GPT-5.4 for agentic tasks?
GPT-5.4 scores higher in agentic tasks (66 vs 64 on the category index, where 50 is average).
Which is cheaper, GPT-5.2-Codex or GPT-5.4?
GPT-5.2-Codex is cheaper: $4.81 against $5.63 per million tokens, blended at three input tokens per output token.
Which is faster, GPT-5.2-Codex or GPT-5.4?
GPT-5.4 streams faster: 129 against 25 output tokens per second.
Which has the larger context window?
GPT-5.4 accepts more context: 1.1M against 400k tokens.