Top-tier GPT-5.1 Codex route used when direct OpenAI is unavailable.
Added Dec 4, 2025
Context Window
400.0K
Max Output
128.0K
Input Price (Auto)
$2.50/1M
Output Price (Auto)
$20.00/1M
Cache Read (Auto)
$0.25/1M
Capabilities
Benchmarks
Benchmarks
Performance metrics and benchmarks
Sourced from Artificial Analysis.
Intelligence Index
35.6
Reasoning
GPQA Diamond
Graduate-level scientific reasoning
86.0%
Better than 84% of models compared
HLE
Humanity's Last Exam
25.7%
Better than 81% of models compared
IFBench
Instruction-following benchmark
70.0%
Better than 84% of models compared
T²-Bench Telecom
Conversational AI agents in dual-control scenarios
83.0%
Better than 73% of models compared
AA-LCR
Long context reasoning evaluation
69.0%
Better than 77% of models compared
Coding
SciCode
Python programming for scientific computing
40.2%
Better than 71% of models compared
Terminal-Bench Hard
Agentic coding and terminal use
34.8%
Better than 80% of models compared
LiveCodeBench
Contamination-free coding benchmark
84.9%
Better than 96% of models compared
Math
AIME 2025
American Invitational Mathematics Examination 2025
95.7%
Better than 97% of models compared
Knowledge
MMLU-Pro
Professional and academic subject knowledge
86.0%
Better than 94% of models compared
Last updated Aug 16, 2026
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