GPT-5 Codex is a coding-focused variant of GPT-5 built for interactive development and long-running, autonomous engineering work. It excels at feature implementation, debugging, large-scale refactors, and code review, with higher steerability and tighter adherence to developer instructions for cleaner, production-ready code.
Context Window
256.0K
Max Output
32.8K
Input Price (Auto)
$1.25/1M
Output Price (Auto)
$10.00/1M
Cache Read (Auto)
$0.13/1M
Capabilities
Benchmarks
Benchmarks
Performance metrics and benchmarks
Sourced from Artificial Analysis.
Intelligence Index
15.3
Reasoning
GPQA Diamond
Graduate-level scientific reasoning
68.6%
Better than 53% of models compared
HLE
Humanity's Last Exam
5.8%
Better than 45% of models compared
IFBench
Instruction-following benchmark
45.0%
Better than 52% of models compared
T²-Bench Telecom
Conversational AI agents in dual-control scenarios
0.0%
Better than 3% of models compared
AA-LCR
Long context reasoning evaluation
63.7%
Better than 81% of models compared
Coding
SciCode
Python programming for scientific computing
37.8%
Better than 68% of models compared
Terminal-Bench Hard
Agentic coding and terminal use
12.9%
Better than 50% of models compared
LiveCodeBench
Contamination-free coding benchmark
54.3%
Better than 61% of models compared
Math
AIME 2025
American Invitational Mathematics Examination 2025
48.3%
Better than 47% of models compared
Knowledge
MMLU-Pro
Professional and academic subject knowledge
82.0%
Better than 78% of models compared
Last updated Jun 28, 2026
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