GPT-5.2 Codex (xHigh) — benchmark results
GPT-5.2 Codex evaluated at the xhigh reasoning-effort setting. Provider: OpenAI. Released 2026-01-14. Access: API.
Unified ELO 1882 ± 29, rank #78 of 1776 rated models, from 37 benchmark results.
Strongest benchmark results
| Benchmark | Score | Metric | Percentile |
|---|---|---|---|
| AA Long Context Reasoning | 75.67 | Accuracy (%) | 100 |
| Context-Bench Filesystem | 93 | Rubric Score (%) | 100 |
| AA SciCode | 54.63 | Accuracy (%) | 97.6 |
| AA IFBench | 77.62 | Accuracy (%) | 96.4 |
| BinaryAudit | 90.67 | Avg Success Rate (%) | 96 |
| AA GPQA Diamond | 89.9 | Accuracy (%) | 94.1 |
| AA Omniscience - Health | 39.1 | Accuracy (%) | 92.5 |
| AA Humanity's Last Exam | 33.46 | Accuracy (%) | 92.4 |
| ALE-Bench | 1299.9 | Performance (Self-Refine x1) (self-reported) | 92.3 |
| AA Omniscience - Software Engineering (SWE) - Kotlin | 60 | Accuracy (%) | 92 |
| AA Omniscience - Software Engineering (SWE) - Dart | 52 | Accuracy (%) | 91.4 |
| Artificial Analysis Intelligence Index | 40.14 | Intelligence Index | 90.2 |
Interactive version: theaggregate.ai/model?slug=gpt-5-2-codex-xhigh · How the rankings work · Data refreshed daily, snapshot 2026-07-22.