OpenAI

GPT-5.1 Codex Max

#3SWE-rebench

by OpenAI

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About

GPT-5.1 Codex Max, released by OpenAI in November 2025, is an enhanced coding variant from the GPT-5.1 Codex line, designed for more complex software engineering tasks requiring additional reasoning depth. It targets large-scale code generation, automated refactoring, and sophisticated agentic development workflows.

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Timeline
ReleasedNov 19, 2025
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License & Family
License
Proprietary
Performance Overview
Performance metrics and category breakdown

Overall Performance

2 benchmarks
Average Score
54.4%
Best Score
60.4%
High Performers (80%+)
0

Top Categories

Coding
54.4%
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All Benchmark Results for GPT-5.1 Codex Max
Complete list of benchmark scores with detailed information
Terminal Bench 2.0
Coding
60.40
60.4%
Unverified
SWE-rebench
Coding
48.50
48.5%
Unverified
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Resources